The psychology of learning; an advance text in educational psychology

Contents

I The nature of learning 1

II The learning curve 16

^_ III Economical learning 36

Preface

In this book I have tried to state every thing that is known about learning. All the experimental work that throws any light on the nature of learning has been carefully examined, and in the light of the experimental results I have endeavored to give the present impartial verdict of educational psychology. Throughout, I have tried to keep within the facts. When the evidence does not warrant a definite conclusion, I say so. The few cases of theory and speculation are plainly labeled as such. The practical significance to the teacher of the facts discussed is pointed out.

The successful use of this book will depend upon two things : first, experimentation ; and second, application. Educational psychology is an experimental science. All its facts come from experimentation and careful observation. These facts, whenever possible, should be demonstrated or illustrated by class room demonstrations and experiments, or by experiments and observations outside the class room. Directions for demonstrations will be found throughout the book, but the teacher must use his own ingenuity in adapting the experiments to his needs and in devising others. And always, the facts must be carried over to their practical application. The students must see the source of the facts and the use of the facts in teaching. The book contains many tables and figures. The mastery of the book will depend upon an understanding of the meaning and significance of the tables and graphs.

W. H. P.

Chapter I. THE NATURE OF LEARNING

What is learning? What are its results? After we have learned, in what way are we different from what we were before? After a child has been in school for a few years, he can read, write, spell, and perform various other acts. He also knows that Columbus discovered America, that George Washington was our first president; he knows the name of his country, of his state, and of our nation ; he knows many other facts in geography, history, arithmetic, and the other branches of study, and many hundreds of other facts that he has not learned at school and that may not be in any organised branch of study. The difference in the child that has come from learning, then, is that he can do things and knows things that he could not do and did not know before. He has knowledge and habits that he did not possess before. The results of learning, therefore, are knowledge and habits. And from the point of view of its results, learning may be defined as the process of forming habits and acquiring knowledge. This, however, is but a superficial statement of the facts. We must know the nature of knowledge and of habits before we can understand the nature of learning.

Habits. — A habit is an act following with more or less regularity upon the presentation of a definite stimulus, to which it has become coupled through experience. Writing, reading, and spelling are such acts. In writing, the stimulus is the idea of the word to be written. The movements of the arm and hand in writing the word constitute the response. In reading, the stimulus is the perception of the printed or written characters. The response, in oral reading, is the movement of the various organs of speech. In spelling, the stimulus is the idea of the word to be spelled. The response is the movements of the hand and arm in writing the word, or in oral spelling, the movements of the organs of speech as in reading. In all habits, the stimulus is either a perception or an idea. The response is muscular movement. When we say the stimulus is a perception or idea, we mean the cortical excitation which is the physiological correlate of the idea or perception. Throughout this book we shall speak of ideas in this v/ay without committing ourselves to the doubtful theory of interactionism. We believe that in a scientific psychology mental processes must not be used as elements in a causal series. When we so use them it is for simplicity of statement, and with the understanding that the cause indicated is the brain action and not the mental process.

Knowledge. — Knowledge is also a special form of organised experience. Suppose, for example, I am sitting at my desk writing and become cold. The idea comes to me that coal should be put into the furnace. I know that if coal is put into the furnace and the draft of the furnace is opened, the room will become warm and I will become warm. This knowledge is the result of experience. Just as in the case of habit, a definite response — action — follows upon a definite stimulus, so also in the case of knowledge, an idea follows upon another idea or upon a perception. In both cases, the definite sequence is due to experience, and usually to repeated experience. At any rate, the repetition of the experience makes the sequence more probable. We may now define learning- as the process of coupling responses with stimuli, and ideas with ideas or perceptions. It is the establishing of definite sequences in the passage of stimuli into responses, or in the passage of perceptions or ideas to other ideas.

An Objective Consideration. — A strictly objective consideration reduces both forms of learning to one. If we study another person to ascertain the results of learning, we find only definite forms of behavior following upon definite situations. For example: if we ask a child to take pencil and paper and write the word America, he takes his pencil and makes the proper letters in the proper sequence. If we ask him to tell us the name of the largest city in the United States, he says the proper word. In answer to our questions, we get from the child always some form of action, as movement of the hand in writing, or of the tongue and mouth in speaking, or merely a nod or shake of the head in assent or dissent. Briefly, we learn in an obective study only about behavior. If we study ourselves, however, we can see a difference in the results of learning. We may sit perfectly still in our chair and have the idea Napoleon followed by the idea General of the French Revolution. There need be no movement of any muscle of the body involved in the sequence. It may be that the idea General of the French Revolution is followed sooner or later by muscular movements, but such movements, even granting that they take place, have nothing to do with the above mentioned sequence. The only important thing to me who has these ideas is, that they are coupled together. The movements that may follow are not necessary to the sequence itself. The essential thing in knowledge is idea. The essential thing in habit is movement.

It may of course be said that / know nothing of another^s ideas except through his movements. True enough, but he does. It may also be said that ideas are worth nothing to the world except as they issue in movement. This is also true. But my ideas may be worth something to me and not issue in movement. They may give quite as much pleasure and satisfaction as any that issue in movement. Neither the fact that the objective value of ideas depends upon their issuing in movement, nor the fact that we can not know another's ideas except through this other person's movements has anything to do with the existence of the ideas themselves and the connections or sequences that are organised among them. Each of us knows for himself that he has habits and organised ideas or knowledge. This distinction between the two aspects of the results of learning — objective and subjective — is clear, and it is a helpful one to make in our study of the psychology of learning.

Physiological Considerations. — It is evident that all learning is connecting stimulus with response, idea with idea. We have now to enquire concerning the nature of this connection. We have spoken of it above as a sequence, but have not explained the cause of the sequence. The sequence itself is evident, in the case of habit to objective obsei*vation ; in the case of knowledge to internal observation. But why the sequence? What underlies it? Of course it may be said, and truly, that the sequence is detei-mined by repetition of experience. This is the cause of the sequence as one sees it on the outside by objective observation of behavior. But what has happened on the inside, in OUT bodies, to determine the sequence? Now a stimulus, in the simplest cases, is due to the excitation of some sense organ, and a response is a muscular contraction. The excitation passes over a neurone or series of neurones to a muscle or group of muscles and brings about a contraction. The process of learning, in habit formation, consists in doing something that insures, with more or less certainty, that the stimulus shall go to a certain muscle rather than to some other. This doing something consists in reducing the resistance along the nervous route that leads to the proper muscle or group of muscles. Stimulation or excitation passing through the nervous system is guided and directed by nothing other than the various resistances offered by the parts of this system. And learning consists, physiologically, in building up and establishing preferential routes in the nervous system. A preferential route depends upon the fact that this route offers less resistance to the particular form of excitation than do other routes. This smaller resistance is due in most part to previous passages of the same kind of excitation along the same route.

It must be pointed out that preferential i^outes are not fixed and static things, nor absolute and permanently definite. We can never be quite certain as to what route any stimulus will take. It is always merely a matter of probability, for the reason that nervous resistance is subject to great variation, is influenced by many factors, such as fatigue, temporary blood supply in the pai-ts involved, immediately preceding stimulation, other concuiTent stimulation, the feeling accompaniments, etc. In the light of these facts, we should say that learning, in habit-formation, consists in increasing the probability, other factors being equal, that a given stimulus will take a certain course. Learning can probably yievei' insure that a given stimulus will, in spite of all other factors, go over into a certain response. As well as we knov/ our own name, there come times when we can not immediately say it upon being asked. As well as we know to say "eighty one" for the stimulus nine times nine, there come times when we can not immediately do it.

The physiological basis of knowledge is precisely the same as that of habit. Knowledge is a matter of one idea following another idea. Now the reason that a certain idea, as x, follows idea a, is that the cerebral excitation underlying the idea a passes over and causes the excitation underlying the idea x. That the excitation takes this course rather than some other, and brings about the idea x rather than some other idea, as y or z, is due, as in habit, to preferential routes in the central nervous system. From the point of view of the nei*vous system, there is no difference whatever between habit and knowledge. From this point of view, all learning is the establishing of differential resistances in the central nervous system. The paths of smaller resistance have been called "bonds," because, in a sense, they bind together stimulus and response, or idea with idea.

Securing the Initial Connection.-— Learning is connecting, but we must now ask how the connection is first secured. In the case of habit, how does the person who is foiTning the habit get the stimulus to pass over to the desired response in the first place? Suppose we wish to couple the stimulus ''five times five" with th6 response "25," we have only to tell the child to saythat five times five equals twenty-five, and he says it. He is able to say ttventy-five when he wishes, and he can couple it to any stimulus of his own volition. He has long since mastered this response. But suppose it is a very young child and we ask him to make the letter a. We can show him the letter and tell him to make one like it. The perception of the letter may be considered the stimulus. But the child can not immediately make the letter. This is a response which he has not yet mastered. How does he master it? With pencil in hand he continues to make marks on the paper. The results of the first trials may have no resemblance to the letter a. The stimulus being maintained, the efforts continue. Each time the response is somewhat different. Slowly the marks begin to resemble the copy. This form of learning has been named the trial and error method. It is the only method in habit-forming ivhen the movement involved has not already been mastered and coupled with the idea of the movem.ent as its stimidus.

During the early years of infancy the child, by the trial and error m.ethod, is learning to make movements with all the muscles of his body. Especially is he getting control of legs and arms and hands and feet and of the vocal organs. In these early years he learns to make nearly all possible movements with his hands and vocal organs, and these movements are organised with the cortical substrate of their corresponding ideas as their adequate stimuli. This learning is so far advanced when the child enters school, that he can make with some degree of precision, any kind of mark he is shown or told to make. He can also make any sounds he hears or is told to make. These last two statements are not wholly true, for there will be some movements and sounds not wholly mastered. But most of the movements and vocal responses have been mastered, so that little trial and error learning is left to be done. Many of the child's responses will be crude and will have to be perfected through practice. The method of perfecting them is the trial and error method. The fact is, that when a child enters school much learning has already taken place. He has partially mastered most of the responses that will ever be required of him. What remains is to couple these responses to their appropriate stimuli, and this is done by what may be called the ideational method. This method is possible only after the movement involved has been attained by the trial and error method and connected with its idea as its adequate stimulus. As previously explained, when we speak of an idea as a stimulus, we mean the cortical activity which is the neural correlate of the idea.

In the case of knowledge, the initial connection between the ideas is secured by simultaneous experience. If we wish two ideas to be joined together in our minds, so that when one of the two ideas comes, the other follows, w^e must experience these two ideas together. And the oftener the ideas are experienced together, the more surely will one arouse the other. Suppose I wish to teach a child the names of the parts of a flower and the functions of the essential parts of the flower. I show him a flower and tell him its name. The idea of the thing becomes associated with the name through simultaneous experience. I then point out the different floral organs, the calyx, corolla, stamens and pistil. As the child looks at each organ, I pronounce the name of the organ upon which his attention is fixed. In this manner the things and their names become coupled together. Then in a similar manner we couple the names of the parts with the functions of the parts. In knowledge-getting in all its various fields, our only method of connecting ideas together is by experiencing those ideas together in a state of attention. Since an idea can enter into any number of such connections, all of our knowledge becomes connected or related, so that we are able to go from any idea to any other idea through intermediary ideas. For example, horse is connected with buggy through simultaneous experience, similarly buggy with city, city with Athens, Athens with Homer, Homer with the Iliad, Iliad with school, school with a certain classmate, this classmate with death, death with heaven. Similarly all the items of our experience are united so that we can go either directly or indirectly from any bit of experience to any other, although the only method of uniting these bits of experience is through simultaneous experience.

The above account of the method by which stimuli are first connected wdth their responses and ideas with other ideas is objective and to some extent superficial. We have described merely what is seen on the outside. \Vhat goes on inside is not entirely clear. Why two cortical processes which underlie two ideas simultaneously experienced should be so related that when later one of these processes is revived it should revive the other, is not known. Probably two simultaneous brain processes are to some extent one process, and flow into one another, so that they become more or less a unity. If such is the case, then later when one of the processes is revived it revives the other because it is really a part of the other, or rather they both constitute but one process.

In the case of habit, it may well be asked Vv^hy, when a child tries for the first time to make the letter a, whatever the first response, does he not continue to make the same marks over and over again instead of making somewhat different marks at each trial? It is possible that the stimulus changes somewhat with each trial. The child sees that the first result is not the result desired, this very fact makes the stimulus for the second attempt a somewhat different stimulus. Moreover, the resistances along the various possible routes are doubtless not very different so that the slightest change in resistance makes the stimulus take a somewhat different route producing a different result. Probably the fatigue toxins are sufficient to change the resistance temporarily. Possibly also the physiological correlates of the feeling element involved have their effects in varying the resistances and shifting the direction of the excitation. These suggestions are entirely theoretical, and we must confess that we are ignorant of the nature of the neurological processes which constitute the causes which we are seeking. For the present we must be content with the objective statement of facts given above. Fortunately this objective statement is sufficient for our practical purposes.

Function of Habits. — Habit is the basis of efficiency. It insures, as much as anything can insure, that the right response follows upon the appropriate stimulus.

Habit enables us to perform an act with greater accuracy, greater speed, less waste of energy, and consequently with less fatigue. Motor efficiency is impossible except through habit. In whatever field our work may be, whether in carpentry, masonry, farming, blacksmithing, engineering, or cooking, we become efficient only through habituating the processes. There is no other way. It is true that habituation resists change. Through habit we become set and fixed, but this is the price that we must pay for efficiency.

If we consider the function of habit from the mental side, the subjective side, w^e find that habit removes actions to the control of lower cortical levels, relieving the higher levels which are thereby freed for other processes which may go on simultaneously. In other words, habit removes an act from the state of focal attention, leaving the higher attention levels for othev processes. For example, when we are learning to run a typewriter, the operation of the machine demands all of our attention. After we have become expert in running the machine, the mere mechanical work demands little or no attention.

Function of Knowledge. — The chief function of knowledge is to put meaning into the world. The getting of knowledge consists in learning the names of things and the functions of things. It is only the fact that we live a social life and need to communicate with one another that makes it necessary to learn the names of things. If we lived an individual, solitary life, we should not need to know the names of things, therefore the essential thing in knowledge is the coupling of the thing with its functions. Now all things in the world are related, and through experience we leam the functions of things, or in other words, their characteristics, what they do, what v/e can do with them. The world has unity and order in it. Through our experience, we get this unity, this order ; we learn the several uses to which the various things in our environment can be put. For example, Vv^e have experience with a substance which we name 17^071. We learn that it is hard, tough, heavy, that it gets red when heated, white and malleable when heated still more. We learn that we can hammer it till it has a shaip edge and then v/e can cut with it; that we can mould it into various shapes and make it into a multitude of useful instruments and implements. In a similar way we learn of all the substances and organisms of our environment. We come to know the world as it is. This knowledge of the world gives us control of the world. The function of knowledge is, then, to put meaning into the world, and through this meaning to give us control of the world. We build an inner, thought world, which corresponds to the outer world. The closeness of the correspondence between our inner world and the outer world indicates our approach to the truth. If the correspondence is not fairly complete and accurate, we are in error, we can not use the outer world. We can not use it because we do not really know it. We do not have its true meaning.

Plasticity. — By plasticity as uesed here, we mean the ease with which we can be changed, more particularly the ease with which new bonds can be established in our central nervous system. As we grow old we lose plasticity chiefly for the reason that in our earlier years definite responses are established for most of the situations of life. The passage of the same excitation over the same set of neurones, time after time, producing the same action sets up a path which resists change. By the time we have reached middle life, most of the situations of life have occurred repeatedly; forms of response more or less definite have been established for all of them. Therefore, in familiar situations we become more set with each succeeding year. However, we do not lose plasticity in unfamiliar situations, as far as is known, until the decadence of the latter part of life sets in. But after we reach middle life there are not many unfamiliar fields. There are then very few situations which we do not approach with some bias or prejudice. Apart from the resistance of bonds already formed our ability to form new bonds increases up to maturity, and probably does not decrease till after middle age. This statement is based on a comparison of the learning capacity of men and women in their forties with that of children of high school age and younger. In fields wherein men and women are not incapacitated and hindered by virtue of prejudicial bonds already formed they learn as readily as do boys and girls, much more readily than young girls and boys.

Man as the Result of His Learning. — Let us now consider the importance to our lives of habits and knowledge. Thomdike has truthfully said that the most important thing about human nature is that it can be changed. Let us couple with this statement another common saying, namely, that a man is the sum of his tendencies. A careful consideration of these two facts gives us an idea of the importance of education. What we are at maturity depends upon the habits and knowledge that we have. Acquiring these habits and getting this knowledge constitute our education. Whether w^e are a Methodist, Presbyterian or Catholic depends upon our education. Whether we are a repubUcan, democrat or socialist depends upon our education. Whatever motor performances we are capable of depends upon our education. Our ideals of life, of work, of duty depend upon our education. Briefly, all our skill, all our knowledge is merely the result of the bonds that have been formed in our central nervous systems. In a very true sense a man is made. He is the product of all the forces that act upon him, particularly of those that act upon him in his earlier years. We do not mean to minimise the importance of original nature. The same forces do not make the same result out of two different children. W^e can not make the same kind of chair out of pine that we can out of oak, nor can Vvc make the same kind of man out of one child that we can out of another. What we are at maturity depends upon the modifications that have been wrought upon original nature. Bringing about these modifications constitutes our education, and education is important to the extent that these modifications are important. And they are of tremendous importance in the life of every individual. The child comes into the world with a multitude of original tendencies and capacities. Upon these the forces of the environment, of home, school, companions, and the whole animate and inanimate world work, forming and moulding and fashioning the individual into the thing that he is to be, namely a being with a background of feelings and passions and instincts, to which is added a multitude of acquired tendencies to act in definite ways to the various situations of life: a being with myriad ideas all interrelated, each idea coupled with others; a being with ideals, ambitions, desires; a l^eing of hates and loves and jealousies,

— all the resultant of the original tendencies provided by heredity and the forces of the environment that have acted upon the individual. The changes that are wrought in us constitute the results of learning. The investigation of their nature and of how they come about is the purpose of this book.

Chapter II. THE LEARNING CURVE

Progress in learning is ordinarily shown by a curve. We must now see how such curves are constructed, how they should be interpreted, notice the various types of curve, and the laws of learning which they exhibit. We must study also the various factors which enter into them, and which determine their upper limit.

The Construction of a Learning Curve. — The purpose of a learning curve is to show the increase in efficiency due to practice. It is customary to indicate the successive practices on the horizontal axis, as BC in Fig. 1. The scale for the scores is indicated on the vertical axis, AB. The scores are shown by the dots above the numbers on BC which represent the successive practices. The line DE joining these dots is the learning curve. Its rise indicates the increasing efficiency due to practice.

Another method of constructing the curve is shown in Fig. 2. The curve is constructed as follows: Instead of representing successive practices by points on the base, we represent them by successive distances. The scores are represented by horizontal lines, drawn at the proper height and of the same length as the distances on the base which indicate the practices. Either of these forms of curve shows the facts as well as the other, but if curves are to be dra\^Ti with the same axes for purposes of comparison, the form of curve shown in Fig. 1 is more convenient.

Figure 1. Learning Curve. Card-sorting, fifteen boxes, live cards to the box, experiment continued five days, four sortings first day, eight sortings on each succeeding day, 12 subjects. Every sixth record is taken for the construction of the curve. The records are in terms of cards sorted per minute.

Figure 2. Learning Curve. Data same as for Figure 1.

In figures 1 and 2, increasing efficiency is shown by ^ rise in the curves. The curves indicate the amounts of work done in successive equal periods of time. Another method of constructing the curve is to show the amount of time required to do successive equal amounts of work. By this method, increasing efficiency is shown by a fall in the curve. It may be illustrated by the same card-sorting data used in constructing the graphs in figures 1 and 2. In the card-sorting experiment from which this data was obtained, seventy-five cards w^ere sorted into fifteen pigeon holes or card trays. Each tray was numbered, and the cards were numbered correspondingly, five to each tray. At each practice, all the seventy-five cards were distributed. With each practice the time required for sorting the cards became less and less. This is shown in Fig. 3. To convert the data into the form used in figures 1 and 2, the number of cards sorted per minute in each practice was com-

So

Figure 8. Data from same experiment as iu figures 1 and 2. Records in terms of number of seconds required to sort the 75 cards. Increased efficiency is shown by the fall in the curve.

puted. Therefore figures 1 and 2 show the increasing number of cards sorted per minute in the successive practices, v^hile figure 3 shows the decreasing amount of time required to sort the seventy-five cards in the successive practices. In the discussion of learning curves which follows, we shall have in mind the types of cui-ve shown in figures 1 and 2, in which efficiency is shown by a rise in the curve.