CHAPTER II
Early Impression—What is Speech—First Efforts—The Phonograph—The First Record of Monkey Speech—Monkey Words—Phonetics—Human Speech and Monkey Speech
Among the blue hills and crystal waters of the Appalachian Mountains, remote from the artificialities of the great cities, the conditions of life under which I grew up were more primitive and less complex than they are in the busy centers of vast population. There nature was the earliest teacher of my childhood, and domestic animals were among my first companions. Among such environments my youth was passed, and among them I first conceived the idea that animals talk. As a child, I believed that all animals of the same kind could understand each other, and I recall many instances in which they really did so.
My elders said that animals could communicate with each other, but denied that they could talk. As a boy, I could not forego the belief that the sounds they used were speech; and I still ask: In what respect are they not speech? This question leads us to ask another.
What is speech? Any oral sound, voluntarily made, for the purpose of conveying a preconceived idea from the mind of the speaker to the mind of another, is speech. Any oral sound so made and so discharging this function in the animal economy is speech. It is true that the vocabularies of animals, when compared with those of man, are very limited; but the former are none the less real. The conception in the mind of an animal may not be so vivid as it is in the human mind, but the same conception is not always equally clear in two human minds. The fact of its being vague does not lessen its reality.
Expression is the materialized form of thought, and speech is one mode of expression. Every animal is capable of expressing any thought that he is capable of conceiving, and such expression will be found to be as distinct as the thought which it expresses. It is inconsistent with every view of nature to suppose that any creature is endowed with the faculty of thought and forbidden the means of expressing it.
It is true that there are some oral sounds which express emotion—such as pain or pleasure. These may not properly be called speech, although from them we may infer the state of mind attending them; but while they are not truly speech, they appear to be the cytula from which speech is developed. While emotions are not voluntary, they do not exist apart from mind. They are produced by external causes, and the line of demarcation which separates them from more definite forms of thought is a vague and wavering one. Thought may be involuntary, but expression arises from desire, and this is the sole motive of speech.
It is not the purpose of this work to discuss the problems of psychology, except to state the grounds upon which we base the claim that animals possess the faculty of speech; but this is intended as a record of observed facts and from them the psychologist may make his own deductions.
With the ever-present belief that animals could talk to each other, I observed from year to year certain things which tended to confirm it. About sixteen years ago an instance occurred which forever removed from my mind all doubt or wavering. Prior to that time I had observed that animals of the higher orders appeared to have the better types of speech and, concurrent with this belief, I tabulated many facts. In 1884 I made a visit to the Cincinnati Zoölogical Garden, where I was deeply impressed with the conduct of a school of monkeys occupying a cage which also contained a large mandrill. This savage baboon was an evident source of terror to the smaller inmates of the cage. A brick wall separated the cage into two compartments. The one was intended for summer and the other for winter occupancy. Through this wall was a small doorway, large enough to admit the passage of the occupants. I observed that two or three of the monkeys kept continual watch over the conduct of the baboon and reported to the other monkeys every movement that he made. When he was lying still, the monkeys passed back and forth without fear, but the instant he rose to his feet or gave any sign of disquiet the fact was promptly reported by the monkeys on watch to those in the adjoining compartment, and they acted in accordance with the warning. I was not able to determine the exact thing they reported, but the nature of the report was evident, and I resolved to learn more fully its meaning. After spending some hours watching their conduct and listening to the sound which controlled it, I became convinced that what they said was sufficiently definite to guide the actions of those to whom it was addressed. In fact I should have been willing to intrust my own safety to those warnings. After a brief study of those sounds I was able to understand the attitude of the baboon towards his neighbors; and while the warning contained no elaborate detail that I could understand, the nature of his actions was made evident. I observed that a certain sound of warning caused them to act in a certain way, and a certain other sound caused them to act differently.
From this start I determined to learn the speech of monkeys. I did not suspect that the task would be so great as it has proved to be. I did not foresee the difficulties that have since become apparent. Year by year, as new ideas came to me, new barriers arose and the horizon continually widened. Yet I was not discouraged at the poor success of my first efforts. From time to time I visited the various collections of monkeys in this country and even availed myself of those found with traveling shows, hand organs, and elsewhere.
After some years of casual study it occurred to me that the phonograph would be a great aid in solving this problem. It would enable me to make more accurate comparisons of the sounds made by different monkeys; and after duly considering the matter I went to Washington and made my purpose known to Dr. Baker, of the Smithsonian Institution. This at first evoked from him a smile, but after explaining the means by which it was hoped to accomplish the end he looked upon the novel feat as a new step in the science of speech.
Having secured a phonograph, I repaired to the animal house then adjoining the Smithsonian Institution. At that time there were but two live monkeys there, and these were the nucleus around which has grown the present National Zoölogical Park at Washington. These two monkeys were of different species, but had for some time occupied the same cage. I had the female removed from the cage and carried into another room. Then the phonograph was placed near her cage, and by various means she was induced to utter a few sounds which were recorded upon the wax cylinder. The machine was then placed near the cage containing the male and the record repeated to him. His conduct plainly showed that he recognized the sound and understood the nature of it. He searched the horn from which the sounds proceeded and appeared to be perplexed at not finding the monkey that had made them. He traced the sound to its proper source, but, failing to find his mate, he thrust his arm into the horn and felt around the sides of it in the vain hope of finding her. The expression of his face was a study worthy of the best efforts of the physiognomist.
Then a few sounds of his voice were recorded upon another cylinder and were delivered to the female, who showed signs of recognition; but as this record was very indistinct it did not evoke from her the interest which the other had evoked from him.
This is doubtless the first instance in the history of speech that an attempt was ever made to reduce the speech of monkeys to record. While this first experiment was crude and the results were not conclusive, it pointed in the right direction and it inspired to further efforts to find the fountain head from which flows the great river of human speech.
Some critic at that time declared that this experiment could be of no scientific value, because the monkey had been provoked to make the sounds recorded, and the sounds so evoked were only sounds of anger or profanity. It was not a matter of concern to me whether these words were moral or profane, so long as they were speech sounds of a monkey and were so recognized by other monkeys. If a monkey uses profanity, he doubtless has some other forms of speech.
Shortly after this experiment I went to Chicago and made a record of a brown Cebus monkey. This record was of a sound most commonly used by that species. I had no exact idea as to its meaning, but its frequent use caused me to select it as one of their most important words. Having secured this, I returned to New York. There I selected a monkey of the same species and to him reproduced the record. He instantly gave signs of understanding it and replied to it. Again and again this sound was reproduced and he repeatedly answered it. He looked at the horn from which it came, then at the moving instrument, and drew back from them. But as the sound continued to proceed from the horn his interest seemed to awaken. He approached the horn and cautiously peeped into it. The sound was repeated. He thrust his arm into the horn and peeped around the outside to see if he had scared the monkey out. Failing to find him, he again retired from the horn, but responded to the sounds. He appeared to regard the thing with a kind of superstition. He seemed conscious of the fact that there should be a monkey there, but failing to find it he evinced suspicion. I do not know to what extent he regarded this as a spook, but he evidently realized that it was some unusual thing.
In this experiment certain facts may be observed. The record delivered to him nothing but the cold, mechanical sound. The elements of gesture, etc., were entirely eliminated as factors in the problem, so that the monkey had nothing to interpret except the sound. This would indicate that the speech sound of a monkey as well as that of man carried with it a fixed and constant meaning. This conclusion has since been confirmed by ample and varied experiments with mechanical devices of many kinds.
Among the defects observed in this experiment was the fact that I had not provided a means of recording the sound made in reply to the record. Subsequently I secured another instrument to do this. In this manner I obtained a reply, and thus I had the two cylinders for comparison. In like manner I repeated the experiment of delivering the record with one machine and recording the reply with another, until I had secured records of the speech sounds of nearly all the monkeys in captivity in this country. Taking these records at my leisure, I carefully compared and studied them, until I was able to interpret nine sounds of the speech of the Capuchin monkeys, and, incidentally, a few sounds of a great number of other species.
It is quite impossible to represent the sounds of monkey speech by any literal formula, and it is difficult to translate them into their exact equivalent of human speech; but, in order to convey some idea of the nature and scope of that speech, I shall describe a word or two. In the tongue of the brown Capuchin monkey the most important word somewhat resembles the word “who,” uttered like “wh-oo-w.” The phonetic effect is rich and musical. The vowel element which dominates it is a pure vocal “u.” The radical meaning of this sound is food, which is the central thought of every monkey’s life. It does not only mean food in the concrete sense, referring to the thing to be eaten, but it sometimes refers to the act of eating, in which sense it has the character of a verb. At other times it refers to the desire to eat or to the sensation of hunger, in which instance it may be said to have the character of an adjective. But grammatical values depend upon structure, and since the speech of monkeys is monophrastic it cannot truly be said to have grammatical form. All the sounds of this species, so far as I have seen, are monosyllables; and most of them contain but one distinct phonetic. I have therefore described them as “monophonetic.” The word above described is sometimes used with the apparent purpose of expressing friendship, or something of that kind.
Another word which refers to drink, or liquid, begins with a faint guttural “ch,” gliding through a sound resembling the French diphthong “eu,” and ending with a vanishing “y.” The sound is used with reference to drink in much the same way as the other sound is used with reference to food.
So far I have not found any trace of the vowels “a,” “e,” “i,” or “o,” sounded long, but in one sound of alarm emitted under stress of great fear or in case of assault, the vowel element resembles short “i.” This sound is uttered in a pitch about two octaves above a human female voice.
All of the sounds made by monkeys and, so far as I have observed, by other animals, refer to their natural physical wants. They are not capable of expressing intricate or abstract thoughts, for the animal himself has no such thoughts. Their simple modes of life do not require complex thoughts.
A striking point of resemblance between human speech and that of the simian is found in a word that “Nellie” (one of my pets) used in warning me of the approach of danger. It is not that sound elsewhere described as the alarm sound used in case of imminent danger. This sound is used in case of remote danger or in announcing something unusual. As nearly as can be represented by letters it resembles “e-c-g-k.” With this word I have often been warned by these little friends. Nellie’s cage occupied a place near my desk. At night she would always stay awake as long as the light was kept burning. Having always kept late hours myself, I did not violate the rule of my life in order to give her a good night’s rest. About two o’clock one morning, when about to retire, I found Nellie wide awake. I drew a chair near her cage and sat watching her pranks. She tried to entertain me with bells and toys. Without letting her see it, I tied a long thread to a glove and placed it in the corner of the room at a distance of several feet away. Holding one end of the string, I drew the glove obliquely across the floor. When I first tightened the string, which was drawn across one knee and under the other, the glove slightly moved. This her quick eye caught at the first motion. Standing almost on tiptoe, her mouth half open, she cautiously peeped at the glove. Then in a low undertone, verging on a whisper, she uttered the sound “e-c-g-k!” Every second or so she repeated it, at the same time watching to see whether or not I was aware of the approach of this goblin. Her actions were very human-like. Her movements were as stealthy as those of a cat. As the glove came closer and closer she became more and more demonstrative. When at last she saw the monster climbing the leg of my trousers she uttered the sound in a loud voice and very rapidly. She tried to get to the object. She evidently thought it was a living thing. She detected the thread with which the glove was drawn across the floor, but she seemed in doubt as to what part it played in the matter. Her eyes several times followed the thread from my knee to the glove, but I do not think she discovered what caused the glove to move. Having repeated this a few times, with about the same result each time, I relieved her anxiety by allowing her to examine the glove. She did this with marked interest for a moment and then turned away. I tried the same thing again, but failed to elicit from her the slightest interest after she had once examined the glove.
When Nellie first discovered the glove moving on the floor, she attempted to call my attention in a low tone. As the object approached she became more earnest and uttered the sound somewhat more loudly. When she discovered the monster—as she regarded it—climbing up my leg, she uttered the warning in a voice sufficiently loud for the distance over which the warning was conveyed. These facts indicate that her perception of sound was well defined. Her purpose was to warn me of the approaching danger without alarming the object against which the warning was intended. As the danger increased, the warning became more urgent. When she saw the danger at hand, she no longer concealed or restrained her alarm.
Nellie was an affectionate little creature. She hated to be left alone, even when supplied with toys and a super-abundance of food. When she saw me put on my overcoat or take my hat, she foresaw that she would be left alone. Then she began to plead and beg and chatter. I often watched her through a small hole in the door. When quite alone, in perfect silence she played with her toys. Sometimes for hours together she did not utter a word. She was not an exception to the rule that monkeys do not talk when alone.
Although their speech is inferior to human speech, yet in it there is an eloquence that soothes and a meaning that appeals to the human heart.
Briefly stated, the speech of monkeys and human speech resemble each other in all essential points. The speech sounds of monkeys are voluntary, deliberate, and articulate. They are addressed to others with the evident purpose of being understood. The speaker shows that he is conscious of the meaning which he desires to convey through the medium of speech. He awaits and expects a reply. If it is not given, the sound is repeated. The speaker usually looks at the one addressed. Monkeys do not habitually utter these sounds when alone. They understand the sounds made by others of their own kind. They understand the sounds when imitated by a human being, by a phonograph, or by other mechanical means. They understand the sounds without the aid of signs or gestures. They interpret the same sound in the same way at all times. Their sounds are made by their vocal organs and are modulated by the teeth, the tongue, the palate, and the lips. Their speech is shaded into dialects, and the higher forms of animals have higher types of speech than the lower ones. The higher types are slightly more complex and somewhat more exact in meaning than the lower ones. The present state of monkey speech appears to have been reached by development from lower forms. Each race or species of monkey has a form of speech peculiar to its kind. When caged together for a time they learn the meaning of each other’s sounds, but seldom try to utter them. Their faculty of speech is commensurate with their mental and social status. They utter their speech sounds loud or soft as the condition requires, which indicates that they are conscious of the values. The more pronounced the gregarious habits of any species, the higher the type of speech it has. So far as I am able to discern, there is no intrinsic difference between the speech of monkeys and the speech of men.