324 MAN AND BEAST bodily musculature. Once we can establish more definite sys- tems of examining the muscular apparatus we can undoubt- edly watch the rise and growth of both simple and complex language habits, plot their curves, etc., and in every way come to look upon that mechanism as we now look upon the system of bodily musculature. It is probable that in a few years we shall undertake the study of such habits from exactly the same standpoint we now employ in studies upon the acquisition of skill in the human being. This will lead to a clearing up of the misunderstanding which exists concerning imagery. On p. 18 we denied the neces- sity of assuming imagery (1) because there is no way of accounting for it on neurophysiological grounds without doing violence to our conception of brain physiology, (2) for the reason that there is no objective evidence to show that it exists, (3) for the reason that we can substitute for what it is supposed to do a mechanism which is exactly in line with what we have found to exist everywhere else, viz., an enormously developed system of language habits. From this point of view, all organization, no matter what its character, shows directly for what it is worth in the appropriate muscles. At present we are told to believe that there are two distinct orders of organization, that which can be read off by the observer directly in the muscles or groups of muscles of his subjects, and that which can be read off only by the subject in which the movement is taking place. This latter organization con- sists of visual, auditory, tactual, etc., copies (substitutes for the stimulus which leads to the response of the muscles), copies and symbols of various kinds of the move- ments themselves (see James' sj^stem of " remote cues "). Furthermore, these images can come and go without show- ing necessarily at all in the muscles. On p. 17 we touched upon this matter. We wish to enlarge upon the general position adopted there. The whole matter can be simpli- fied by calling this second type of asserted organization thought (imaginal). The position which we have earlier sketched took the ground that imaginal thought needed no new principles of explanation and required no different LANGUAGE HABITS 325 interpretation in behavior from that of other habits; and that if behavior could adequately treat of the overt bodily organization, it could, by the same principle, just as ade- quately treat of the thought processes. Unfortunately language habits have not been studied from the standpoint of behavior and we have little data of a positive kind which will bear out our assertion. Anna Wyczoikowska in her work on the speech mechanisms states that when a subject was told to think of a word or sentence, there followed a definite movement of the tongue, and that sounding the word or sentence within the range of the subject also produced a tongue movement. Unfor- tunately her work stops far short of showing what we believe exists. If it could be shown that the sentence, '' Mary had a little lamb," when spoken in front of the subject, produced a very definite form of movement (habit), and the same general type of movement followed when the subject was told to think the words (they need not be identical in form), the evidence would be favor- able. Her records are not treated in this way and too few were made on any given subject. Furthermore, no time relations are shown. We give (Figs. 56-60) some of the curves presented in her paper. Explanatory legends attached to each will show to what the curves refer.
The tongue is a poor organ to deal with: we need to get some direct way of observing the vocal cords, throat forma- tions, etc. It will be extremely difficult to get definite evi- dence either for or against the present theory. In the section below we shall see that there are forms of language habits other than those appearing in the vocal apparatus. For this reason it is clear that robbing a man of the laryngeal mechanism would not rob him of thought, since usually in those cases in which a man has been robbed of this apparatus there has been a tumorous or cancerous growth that has been slow in its onset, and for this reason bodily language habits have grown up. Furthermore, even in cocainizing the vocal apparatus, we do not destroy the possibility of throat and laryngeal movement. Only the sensory nerve endings in the mucous membranes will be MAN AND BEAST LANGUAGE HABITS touched by the cocaine. The deep-lying sensory endings of the muscles which are the only essential (sensory) ones from our point of view, will not be affected by the cocaine.
If we could find a case where a man suddenly lost his laryngeal apparatus without any serious injury to the other bodily mechanisms, we should have a crucial case.
From our point of view there would be, or ought to be, a serious limitation in this man 's thought processes. It is extremely unlikely that such a case will ever occur. We have had under consideration many methods which might words e, spoke M-M.
Hr Pfr Ci o M lead to the closer observation of the movements of the vocal mechanisms. It probably would be premature to give any sketch of these. As stated above, Madam Wyczoikowska shows one method which, imperfect as it is, 328 MAN AND BEAST 328 MAN AND BEAST presents some of the things which we believe to be true in every case of thought. Even that unsatisfactory method can be refined and made to give facts which will either support the argument here presented or else show its un- soundness. To advance the argument, which we admit is highly speculative, we will suppose that future analysis will enable us ultimately to show that every word, syllable, and letter, whether spoken or thought, produces a charac- teristic form of response which, when recorded, must be looked at from the same standpoint which we adopt when looking at habits elsewhere. At present we can take a human being or an animal and in a shorter or longer time get a fairly complete record of his bodily habits, i.e., of their number, of the accuracy in each, of their complexity, the ease with which habits are formed, etc. This does not mean that we ever have done this or that we ever will do it in any complete way, but there is nothing theoretically impossible in the problem. ^ In the same way we should be able to determine man's language habits, what habits are being used at the moment (i.e., what thought processes are going on), etc.
The nature of language habits. — Not all habits formed in the vocal cords are true language habits. The parrot and many other birds learn to speak and sing words; the dog even may possibly form certain vocal habits. If we turn to the child we find the genesis of such habits. The child begins with certain sounds that are essentially instinctive, — " ma-ma-ma, gu-gu, goo-goo," the guttural or velar r (h) is also common, etc., differing slightly in different races. His first simple vocal habits depend upon the language which surrounds him. For a long time such habits in the child do not differ from those formed by the 2 Practically, however, the technical difficulties are very grave indeed. On the possibility of recording and reading sounds of the human voice, musical instruments, etc.. see the article "Vocal Sounds," by John Gray M'Kendrick and Albert A. Gray, in Schafer's Text-Book of Physiology, p. 1206. For a recording device see an article by M'Kendrick,' "Demonstration of an Improved Phono- graphic Recorder, and Remarks on the Curves Thereby Obtained," Proceedings of Edinhiirgh Royal Society, 1895, XXI, p. 194.
LANGUAGE HABITS 329 parrot. The vocabulary of the " parrot stage " in the child may be fairly large, consisting of as many as a hundred or more words. By the time this stage is reached the child is ready to begin the process of forming true language habits. Vocal habits do not become language habits until they become associated with appropriate bodily habits, and even substitutable for these acts. If we examine the bodily habits which have been formed prior to this time we find that the use of the hands, arms, and fingers, organs of locomotion, etc., has been more or less perfected, i.e., hundreds of habits of response to objects have been formed. The child has learned to respond by appropriate acts to its doll, bottle, small boxes, and to hundreds of other objects. These habits of response to objects are essential to the formation of language habits. So far the animal and the child are on the same basis. The parrot responds with words to an auditory stimulus, or to an intra-organic stimulus (spontaneous words of the parrot): that animal can also form habits of opening boxes, etc. What, then, constitutes the difference between the parrot and the child? They are not different at this stage! If we watch the development of the child from this point on, however, we find that the next step he takes car- ries him to a plane to which no animal has risen. The stimulus (object) to which the child often responds, a box, e.g., by movements such as opening and closing and putting objects into it, may serve to illustrate our argu- ment. The nurse, observing that the child reacts with his hands, feet, etc., to the box, begins to say " box " when the child is handed the box, '' open box " when the child opens it, " close box " when he closes it, and ^^ put doll in box " when that act is executed. This is repeated over and over again. In the process of time it comes about that without any other stimulus than that of the box which originally called out only the bodily habits, he begins to say '^ box " when he sees it, ^' open box '' when he opens it, etc. The visible box now becomes a stimulus capable of releasing either the bodily habits or the word habit, i.e., development has brought about two things: (1) a 330 MAN AND BEAST series of functional connections among arcs which run from visual receptor to muscles of throat, and (2) a series of al- ready earlier connected arcs which runs from the same recep- tor to the bodily muscles. When the box is presented now, which set of arcs will function? Evidently either (1) or (2) or both simultaneously. It is at this time that the influence of the environment upon shaping the language habits comes again clearly to the front. The object meets the child's vision. He runs to it and tries to reach it and says "box." The box happens to have been put beyond his reach. The nurse, seeing the child's efforts to reach it and hearing the word " box," hands it to the child. This situation being repeated day in and day out, not only with this object but with hundreds of others, brings it about that the arcs running from receptor to throat muscles offer the least resistance so far as concerns the neural impulses aroused by the box (frequency, p. 262). Finally the word is uttered without the movement of going toward the box being executed. There has been a substitution (mechanical process) of a language habit for a bodily habit. One other step and the process is complete. We found in our studies on the maze that every cut de sac represented what we might call a simple unit habit. These simple habits when perfected arise serially. When learning is complete we can put the animal down anywhere in the maze, and after a few trial movements the remaining part of the journey is executed without a break. Something similar of course occurs in all complete systems of bodily habit and in language habits as well. Habits are formed of going to the box when the arms are full of toys. The child has been taught to deposit them there. When his arms are laden with toys and no box is there, the word habit arises and he calls '' box;" it is handed to him and he opens it and deposits the toys therein. This roughly marks what we would call the genesis of a true language habit. The expositions of the formation of these simple habits are often put in unscientific form, e.g., language is said to be social and words arise only in virtue of the fact that man is a social being. It probably is perfectly true that LANGUAGE HABITS 331 if the child were taken at birth to a desert island and fed by the ravens (granting the climate were kindly) that no true language habits would be formed. Certainly none which would characterize the adult reared under such circumstances as belonging to any known nationality. We have no objection to saying that language is social in its essence, provided we recognize the essentially mechanical nature of the formation of such habits. In the same way a human being reared in a world in which no monochro- matic lights were present would never form habits of reacting differently to differently colored objects, the rea- son being that no stimulus would be on hand to call out such responses. In the same way no true language habit (laryngeal) would be formed by a normal child dwelling in a community of deaf mutes. No stimulus would be at hand to call out the response in such a way as to force the formation of the habit. It is essential to recognize that the process of forming the language habit of ' ' box ' ' would probably advance just as quickly if the " Tik Tok Man of Oz ' ' were put in as a nurse and his mechanism so arranged that he would speak at the right time and move the box in the right way at the right time.
Early predominance of language habits. — It is not our purpose to treat the steps by which such habits are de- veloped. We are interested simply in the steps by which one such habit might arise. The moment the child forms the first language habit, he is forever differentiated from the beast and henceforth dwells apart in another world. He still uses his bodily habits, certainly, but not even a stroke of paralysis, paralyzing all other skeletal muscles except the laryngeal ones, could rob him of his right to be called a human being.
Forms of language habits. — It is immediately suggested that there are many deaf mutes in the world and many pathological subjects lacking a sufficiently developed throat mechanism for the formation of language habits. It would be impossible to enter into any detailed study of the various forms which language habits may take. JWe can, however, at least mention some of the principal 332 MAN AND BEAST forms. We have (1) the typical process sketched above where the word either uttered aloud or uttered in silent speech (thought) sets up a stimulus which effects a re- sponse in the musculature of the arms, legs, trunk, etc., or else initiates another word, which may in a similar way serve as a stimulus to arouse a bodily habit. This re- ciprocal process of bodily acts arousing the (thought) word: the word or series of words arousing another act, etc., is persisted in during the whole of the waking day and, if the psychoanalysts are right, during most of the period of sleep. In sleep, however, since the body muscles are largely inert, the drama as a whole must be played with the larynx as the stage.^ It should be emphazised here that in adults the situation (sum of present extra- and intra-organic stimuli) determines whether the thought or spoken word will serve as the stimulus for a bodily act or for another word. In reverie the bodily muscles are re- laxed and (thought) word initiates (thought) word; at an afternoon tea or at a reception where the words or phrases are stereotyped, the heard word initiates a series of overtly spoken words on a par with the bodily habit of walking. When the situation is changed to scenes of action, the emphasis falls again upon the bodily muscles. Strenuous objections naturally arise to the viewpoint just expressed. It is asked, " Do we always think in terms of words? " We should certainly reply in the negative. Observation shows that we have even short-circuited (substituted for) the word system of thought.* We find (2) a somewhat ^ It should be a relatively easy matter now to test whether, e.g., the related tongue movements are present in sleep.
* In this connection it will be instructive to glance for a moment at the complexity in habit systems with which we have to deal in daily life. We may illustrate this in a very easy way by a suitable example: before me as I write is a calendar with "Friday, January 9 " upon its face. The habit of tearing off these leaves has been forced upon me in past years. The effectors of hand and arm are used in this operation. The city bell rings 12 p.m.. I say aloud "another day over, it's January 10! " I glance at the calendar and say aloud, " tear off leaf." Immediately the movement is executed. Two stimuli are present simultaneously, both of which act upon the same effectors, viz., the intra-organically aroused one (exercise of the throat muscles) and the one extra-organically aroused, i.e., by EARLY DEVELOPMENT OF LANGUAGE 333 highly involved system of language habits which, strange to say, while formed (as we believe) after vocal language habits, have their locus in the general bodily musculature such, e.g., as the nod of the yes or no, closing the lids slowly for yes, winking, which expresses a whole series of words, the shrug of the shoulders, and bodily sets and attitudes. These movements are often spoken of as being mimetic. ° But the fact is they have nothing at all to do with thought, until by a process of substitution such as we have already described they come to function as do words. The muscular movements originating in these groups can arouse there a stimulus which incites to response, e.g., to an extension of the arm, bringing about the removal of the leaf of the calendar in our illustration. Since these mimetic movements often follow, are reflexly aroused along with movements in overt or silent speech, it is perfectly natural to suppose that a substitution process could occur the spoken word. The reaction must follow equally well if another spoke the word (even if I were lacking in a laryngeal language apparatus). On the other hand, I may think the words "Saturday, January 10, tear off leaf," and the act will follow. (It is just at this point that the upholders of the image say that you can not only think it by silent speech, but that you can also imagine the act and the movement will follow. Our contention is that in thought the words must be uttered silently before the habitual act arises. See also p. 324. Neural activity begins always in a receptor, in this case in the vocal cords. What starts movements in the vocal cords? A previous movement in the cords or another form of stimulation, either intra- or extra-organic ). Of course, since the act is habitual and was formed prior to the language habit, a word is not necessary to initiate the act. If I were blind and had no speech the sound of the bell might release the act of extending the hand and tearing off the leaf (if I may, by courtesy, be allowed to suppose now that the calendar has become one of the raised letter type). Finally the act might follow in the absence of the bell. If I were a blind deaf mute and happened to feel my watch at 12, I might be led to extend my hand and arm and tear off the leaf. It is clear that if a suitable stimulus is at hand, the act of the hand and arm follows. Now this stimulus can have its origin in any receptor (or in any muscle, considering them now as receptors ). We have found such a group of receptors to be the throat muscles themselves, i.e., the movement of these muscles, as in the silent speaking of the word, will initiate the impulse which drives the muscles of the arms and hands. All such processes are at bottom really identical in nature. ^ Sante de Sanctis: Die Mimik des Denkens.
334 MAN AND BEAST by which they Avould come to function independently of the word. Of (3) writing habits, (4) deaf and dumb sign language, and (5) formation of words on lips we say nothing, since the processes involved here are all essen- tially upon the same plane.
Futility of searching for reasoning, imagery, and the like in animals. — From our point of view it can readily be understood that the search for reasoning, imagery, etc., in animals must forever remain futile, since such processes are dependent upon language or upon a set of similarly functioning bodily habits put on after language habits.
Division of labor between human and animal behav- iorists. — If the highly speculative position we have tenta- tively put forth here represents in any measure the true state of the case, it would seem that the field of behavior could be divided largely among three groups of investi- gators: (1) a group interested in the instincts, sensory and motor habits of animals below man, (2) another group interested in the same type of problems in the human being, and finally (3) a group interested mainly in the language habits of the human being and in the possible development of such habits in the anthropoids.
BIBLIOGRAPHY Jennings, H. S., Behavior of the Lower Organisms. New York, Columbia Univ. Press, 1906. JuDD, C. H., Psychology. New York, Seribner's, 1907. Wither, Lightner, " A Monkey with a Mind," Psych. Clinic, 1909, Wyczoikowska, Anna. Op. cit.
CHAPTER XI VISION Introduction. — I. Limits of spectral sensitivity and relative stimu- lating effect of different regions of the spectrum. — Mammals. — Birds with day vision. — Birds with twilight vision. — Hess' ab- sorption theory. — In fish. — In reptiles and amphibia. II. Dark- ness-adaptation: white light. — Introduction. — Darkness-adapta- tion in birds with daylight vision. — In birds with twilight vision. — In fish. — In reptiles and in amphibia. III. Darkness-adapta- tion: monochromatic light. — In birds. — In reptiles and in am- phibia. IV. Sensitivity to wave-length. — In mammals. — In birds. — Demonstration of the Purkinje effect. — Results from a physiological method of testing for color sensitivity. — ^Mimicry or adaptation to background no test of color sensitivity. — In rep- tiles and in amphibia. — Delicacy of the problems in color sensi- tivity. V. Response to white light. — Mammals. — Birds. — Fish. — Amphibia, and reptiles. VI. Response to form and size. — In mammals. — In birds. — In reptiles and in amphibia.
Introduction. — Yery little of the early work on the re- sponses of vertebrates to light was conducted with sufficient care to give reliable results. This is especially true where monochromatic lights have been used as the specific stimuli. In reading the summary of results given here it must be remembered that this department of behavior is a very active one and what is said should be considered as por- traying only the present conditions of affairs. We have to admit that many of the conclusions appearing here are in need of confirmation.^ I. Limits of Spectral Sensitivity and the Relative Stimulating Effect of Different Regions of the Spectrum Mammals. — The majority of mammals tested under ex- perimental conditions are insensitive to light of long wave- lengths. At least for them such rays have a relatively low ' This summary of the color work makes no pretense of being exhaustive. It does not embrace all of the results upon any given 336 VISION stimulating effect. The following mammals have been under observation: The dancing mouse, white rat, hooded black and white rat, rabbits, and monkeys. The range at the red end cannot be given in terms of w^ave-length. There has been no satisfactory experimentation upon the range at the violet end. It is probable that the shorter rays of the spectrum have a relatively high stimulating value. Tests upon rats and rabbits show that the blue and green have a relatively high stimulating value as compared with the yellowish-red.
Birds with day vision. — From C. Hess we learn that when a light-adapted chick is taken into a dark room and placed before grains illuminated by the whole spectrum (spectrum of medium intensity) and allowed to peck freely, it will begin with the grains illuminated by the red and orange rays. It pecks continuously until the blue-green region is reached, beyond which point it refuses to peck further. A well dark-adapted chick in a spectrum of the same intensity will always begin to peck at the grains il- luminated by the red; then in order, orange, yellow, green, and blue-green. While under these conditions the spec- trum is widened at the short end (i.e., while the birds may peck further into the green) they still refuse to pick up the grains illuminated by the blue and violet rays. The behavior of the pigeon under the same conditions is closely similar to that of the chick. The range at the red end for it is normal, but at the violet end it is even more contracted than is the case with the chick. Chicks 48 hours of age have the same spectral range as the adults. In a spectrum of low intensity they feed first in the region which has the highest stimulating value for the human eye. This in the chick is shifted somewhat towards the red end. In connection with the author's work upon the homing sense he has determined the limits of sensitivity at the two ends of the spectrum for the dark-adapted (not complete) chick (90 days of age.)"
form, nor does it trace such studies consistently through the va- rious phyla. This two-fold selection process is necessitated by the volume of the work done and its relatively unsatisfactory nature. ^ This summary is taken from a work as yet unpublished. It SPECTRAL RANGE OF CHICK 337