Essentials of psychology

Preface

It has long been a favorite theory of the author that even the more profound subjects are capable of comprehension by the average high-school student, if presented in the simplicity of the truth. It is in accordance with this theory that this book has been prepared.

For several years it has been the author's privilege and pleasure to lead a class, varying in numbers from twenty-five to forty, through the delightful paths of psychological science. The main difficulty has been in securing a text-book .that would give just what was needed, and allow at tfie' same time that privilege which all intelligent beings should enjoy — a privilege too often lost sight 'bf in the preparation of text-books — the privilege of doing a little independent thinking. The condensed editions of the_ longer treatises seemed to retain too much of the university flavor, too much of the philosophy of the subject, while for a psychology suited exactly to the needs of the normal and high school there seemed to be a growing demand. With iv PREFACE.

the intention of gratifying the author's own pupils, and many friends of more advanced age, and with the hope that in so doing he might also reach the wants of others, the preparation of this little book has been undertaken.

The author disclaims any great originality in the subject-matter. Indeed, with such writers in English in the field as James, Sully, Ladd, and many others, to say nothing of numerous German authors, originality would seem to be hardly possible. The method of treatment, the choice of the subjects treated, and the order of treatment are, however, so far as he knows, his own.

It is hoped that the style which has been adopted will meet the wants of students in high and normal schools, and at the same time will not seem too familiar for that large number of people who are anxious to learn something of Psychology in connection with their ordinary reading. The paragraphs have been arranged with special reference to the needs of the student, and the side-heads will suit his convenience in reviews, and also permit the use of the topical method.

The author has found himself constantly tempted to a fuller discussion of many topics, but, having set the limits beforehand, has rigidly held himself within bounds.

PREFACE. V

The questions and problems, some of which may seem trivial, others too difficult, will be found to render valuable assistance in attaining one of the objects of the book, the development of the psychologic faculties of the student. All these questions and problems, as well as the illustrations and examples, — which are very few in number, — are but suggestive in character, and will, of course, be supplemented by those who may use the book. Doubtless some assistance will be needed occasionally, but it should not be given until the student has failed to answer for himself; for "A man's reach should exceed his grasp."

In order that the results of independent investigations may be rendered permanent, a number of blank pages will be found at the end of the book, following the index, upon which the student may note his conclusions.

The author expresses his thanks to all those who have assisted in the preparation of this book. Especial mention should be made of Prof. William James, of Harvard, who has made several valuable suggestions, and of Dr. A. F. Blaisdell, who has kindly permitted the use of several cuts from his Practical

Physiology.

COLIN S. BUELL.

Introduction

During the last few years changes in the methods of studying Psychology have taken place, which, because of their nature and extent, have 2fiven rise ^ ., ^ , .

' ^ Two Schools of

to the terms ''Old Psychology" and ''New Psychology. Psychology." It may be well for us to know, at the outset, what these terms mean.

The term "Old Psychology" is applied to the work of all the students of this science whose methods were based upon observation, introspective or ex- ^,, „ ^,

^ ' ^ Old Psychology

ternal, followed by speculative reasoning, defined, thus being more closely allied to speculative philosophy or metaphysics in many respects than to psychology proper.

The psycholoo;ist of the old school ,, , , ^ ^,,

^ -^ » Methods of Old

needed only an occasional glimpse into Psychology, the outside world. He could shut himself up in his study, and, being himself both observer and observed.

could spin his theories upon the nature of mind and the causes of its peculiar phenomena, undisturbed by the fact that other minds in the busy world without might not agree at all, either in the phenomena or in the results of his deliberations upon them. Being thus shut in, he gradually formed a cult all by himself, using his own methods and his own peculiar forms of ex- Resuits of the prcssiug his idcas. As a result, this most methods. interesting of all sciences became a sealed

book to common people, who could not spare the time necessary to master the vocabulary and the intricacies of psychological speculation.

The ''New Psychology," on the other hand, is „ ^ , the term applied to the science as de-

New Psychology ^•'•

defined. vclopcd by mcaus of accurate investiga-

tions and measurements.

The psychologist of the new school takes nothing for granted. His study is a workshop and laboratory combined, wherein may be found numberless delicate Methods of New ^ud costly instruments for testing and Psychology. mcasuring the intricate processes of minds, both those of human beings and those of the lower animals. His results are expressed in the language of the common people. He is all the time in search of new material, and any person who visits his workshop is liable to be made the victim of some kind of experiment.

These delicate and costly machines would seem to be as effective in excluding common mortals from the study of this subject as were the methods p^^^^.^^^^^^^y ^j of the old school. It is quite possible, "^^ methods

^ for common

however, to make use of the methods of students, the ''New Psychology" in performing experiments within the reach of all, the results of which experiments will serve to elucidate principles, even though lacking the absolute accuracy to be obtained only in the extensive laboratory.

We must not imagine that, because there is a '' New Psychology," the old is therefore obsolete ^,, „ ^ ,

■^ ^J ' Old Psychology

and valueless. The results obtained by the ^*"^ valuable, old methods are remarkable, and, though lacking the accuracy of modern research, are still very valuable. In the following pages we shall find it Method of this necessary to use some of the material fur- ^°^^' nished by the *'01d Psychology," but shall hope to be able to translate it into simple, comprehensible terms.

The word Psychology is derived from two Greek words, '^vxTj meaning soul^ and \6yo^ meaning science, the word soul beins^ understood to include „ , ,

'-' Psychology

all the mental endowments of the human <iefined. being. Make a working definition of Psychology.

The need and value of the study of this science become perfectly apparent when we consider that there are few people who arrive at maturity who have nothing to do with the rearing^ and education of

Need and value

of study of children. The most important and valuable

Psychology.

part of a child is his soul equipment, and it becomes necessary for those of us who are to be in any way responsible for that equipment to know something of the processes and laws of mind development. Parents and teachers especially should be well acquainted with psycholoo-ical laws, for they

For parents and ^ r- j & > j

teachers espe- are dircctly responsible for the children

cially.

under their care, and a mistake made when a child is young is often irreparable. That the matter has received too little serious consideration is attested by the condition of children of all ages in almost every community.

But we should not study psychology only that we may know something of the proper methods of train- More immediate ^^S children. It has a more immediate interest. interest for us, in that it should help us

to know ourselves better, and in this way it should lead us on toward the great end of all education — self-control. Let us bear this fact in mind, and let us judge of the value of the study to us by its effect upon our own mental development.

Let us now consider for a moment the methods by which we may study the human mind. The most obvious method is by carefully observing the actions of others. The states and acts of the mind Methods of show themselves more or less clearly in ^^^'^y*"^ "^^"'^• physical actions, and by observing these actions we may get at the mind behind them. We i. observation, commonly speak of our friends as looking sad or happy, as assuming attitudes of attention or being wrapped in reverie or profound thought. All these acts and attitudes are indications of what is passing in the mind, being the physical expression of the mental state. It is necessary to note. Errors in obserhowever, that there may be several ^^*^°"- sources of error in our observations, and we shall need to be constantly on our guard against them.

Among these errors may be mentioned, first, our own imaginations, which are apt to color and ,. ^^^ ^^^ distort the phenomena observed according ^"paginations, to the natural tendency of our own minds. For example, call upon one of your young woman friends who is the fond mother of her first child. Observe the movements made and the sounds uttered by the infant. You will not need to ask the mother to explain these things, but you will doubtless find that her interpretations hardly agree with yours.

If you are fond of children and your friend is not, it may be of interest to notice the difference in the terms used when speaking of the Httle ones. That is to say,

(2) Prejudice. our pi'ejiidices will often lead us into error. A third source of error lies in the fact that notkmz

(3) Senses easily ^^ easier tJiau to dcceive the senses. We deceived. often say that ''seeing is believing," which might be true if we could only really see. Visit the police court and listen to the evidence. Is it possible that all these witnesses, who flatly contradict one another under oath, are perjurers .''

Next to this method of observation, which is so liable II. Scientific Ex- ^° ^rror, comcs the method of scientific experiment, periment. When we wish to find out any particular fact about the mind, we may be able to bring about the right conditions, and then, by accurate measurements, obtain the results for which we are seeking.

A third method is the introspective method. This III introspec- ^^ ^^^ mcthod commouly used by the old- *^°"' school psychologists who make their own

minds the object of observation and study.

Still a fourth method may be mentioned. We may IV. Reading. study mcutal phenomena in connection with our reading. Indeed, though we cannot perform experiments upon the characters portrayed in books, we shall certainly find the study of literature from the psychological point of view to be far more interesting and helpful than from any other.

We should constantly bear in mind, however, that in all our study of Psychology we have noth-

Psychology does

ing to do with the material or immaterial not deal with

. . nature of mind,

nature of the mmd. That subject may be safely left to the metaphysicians. They may decide that mind is nothing but the physical disturbance of the molecules of the body produced by its contact with the outside world, or that it is the result of a chemical combination of particles of matter, or some other equally plausible physical result. Whatever their opinions, supported by arguments no matter how unanswerable, the mind, fortunately for us, will continue to work in the same old way, and to ^^^ ^^^^ , g_ produce the same results. It is the phe- "°"^^"^- nomena of mental action with which alone we are concerned.

Whatever may be the nature of mind, we know that it has a close connection with and a pecul-

Close connec-

iar dependence upon the physical system, tio" between

mind and body.

It is thus related to the body in two ways : first, its condition depends largely upon the condition of the body, and its action is also dependent upon physical conditions ; on the other hand, it controls and directs the body upon which it so largely depends.

The seat of the human mind is the seat of mind. brain, which occupies the upper portion of the cavity of the skull. The brain being shut in by the bones of the skull, some method of communication with the outside world must be established, in order that the mind may be able to gather materials for its use. No doubt the Creator might have placed the seat of mind in the ends of the fingers, but He did n't.

The pioneers in psychological study said that the

mind came into contact with the outside world at the

surface of the body, but anatomy has

Means of communication with given us more light on that subject. We

outside world.

have found that the nerves furnish the means by which materials may be carried to the mind and by which orders of various kinds may be sent from the mind. These nerves form a complete telegraphic or telephonic system with ramifications throughout the entire body, so that the mind may be readily informed of all that is going on.

. Nerves, as we learn from Physiology and Anatomy, are arranged in pairs. One nerve carries impressions Arran ement of i^^ward toward the brain, while its compan- °®"'®^* ion carries an order from the mind outward

toward the surface of the body. The former are called afferent nerves (Latin ad =^ to or toward, /i?r^= carry), the latter, efferent nerves (Latin ^;ir=: out, /^r(9 scarry). The nerves from the extreme portions of the body seem to be unable to carry an ordinary stimulus to the brain without reinforcement, just as in the case of a message over the long-distance telephone; so there are found, along the lines of the nerves, rein- Nerve ganglia, forcing stations, clusters of nerve cells (Fig. i), called ganglia (sing, ganglion), connected by the nerve fibers which resemble fine silk thread.

Some of these nerve ganglia have a limited power of

Fig. I. Nerve cells from the spinal cord.

acting as little brains, in which capacity they govern the movements of certain portions of the special powers body under the general supervision of the °^ ^"'"^ gangha. mind, very much as a city is given certain powers of home government by the state legislature, in order that the latter may be relieved from some of the minor details of government, and may thus be enabled to devote its attention to more important matters.

lO ESSENTIALS OF PSYCHOLOGY.

Actions which are governed by the lower nerve centers are called reflex. It should always be remembered, when speaking of reflex action,

Reflex action

subject to brain cxccpt in the casc of the sympathetic system (explained under Medulla Oblongata), that all such action is, in the last analysis, subject to and dependent upon brain control.

It is not within our province to go into a detailed description of the nerves and their action. It will be Two parts of the sufficicnt for US, in order that we may nervous system, understand their bearing upon mental phenomena, to divide the nervous system into two parts, giving a general account of the functions of

I. Central. each : I. The Central System, comprising the spinal cord, the medulla oblongata, the cerebellum, and the cerebrum; 2. The Peripheral System, which is

II. Peripheral. Subordinate to the central system, branching out from it into all parts of the body.

The matter of the spinal cord, which is enclosed in the spinal column for the sake of protection, is made „ . , , , up of a central portion of nerve cells and

Spinal cord and t^ ^

its function. ^^ outsidc coating of nerve fibers. Nerve fibers and nerve cells are distinguished by their color, the former being white, the latter gray. The function of the spinal cord is to act as a main channel of communication between the brain and the extremities of the body.

INTRODUCTION.

II

Branching off from the spinal cord are thirty-one pairs of nerves, each having a posterior and an gpinai nerves ; anterior root, the posterior root beins: the ^^^^^ arrange-

^ *^ ment and func-

road by which the message from the extrem- ^^°"- ity reaches the cord and the brain, the anterior root being the road by which an order is sent from the brain to the extremities. These nerves have received names signifying their function in addition to the names given

Fig. 2. Section of spinal cord.

A, anterior fissure ; A ', anterior root ; A ", efferent nerves ; P', posterior root; P" , afferent nerves; G, spinal ganglion.

them above. These names are sensory, which corresponds to afferent, and motor, corresponding to efferent.

Can you give any reason why these names are appropriate }

If the posterior roots of these pairs of nerves should become paralyzed or should be cut, we ^„ , , . .

^ -^ ' Effect of injury

might still be capable of performing all to spinal nerves.

Problem.

our customary movements, but we should be incapable of feeling pain from any injury to the portions of the body traversed by these nerves.

If, on the other hand, the anterior roots should be cut, Problem, what would be the effect upon the person ?

Thus we see how much depends upon the integrity of the spinal cord. If the cord itself is injured, all Effect of injury ^^^ portious of thc body traversed by the to spinal cord, ncrvcs joining it below the injured point become paralyzed, because, the roads of communication to and from the brain being closed, the brain cannot receive sensations nor send orders.

Why is it that a person dies when the neck is broken ? You have doubtless read of those remark-

Probiems. able cascs where the vertebrae of the spinal column in the neck have been dislocated and yet the person has lived. Can you give any satisfactory explanation of the phenomenon ?

The upper end of the spinal cord, as it leaves the spinal column and enters the cranium, is enlarged. Medulla Obion- ^his enlarged portion of the spinal cord e^^*- is called the Medulla Oblongata. The

medulla, while not a part of the brain proper, has been endowed with a very important function in the make-up of the human system.

Under its special care is placed the action of the

INTRODUCTION.

so-called sympathetic system, the heart and blood vessels, the lungs, and the digestive apparatus. Just think in what a critical condition we should constantly be if the action of these organs that we call vital were dependent upon

Function of the medulla.

Fig. 3. Anterior view of the medulla oblongata,

A , chiasm of the optic nerves ; B, optic tracts ; C, motor oculi communis ; D, fifth nerve ; E, motor oculi externus; F, facial jierve ; H, auditory nerve ; /, glossopharyngeal nerve; ^T, pneumogastric ; L, spinal accessory; M, cervical nerves; N, upper extremity of spinal cord ; O, decussation of the anterior pyramids; R, anterior pyramids of the medulla oblongata ; S, pons Varolii.

our thoughtfulness. Some time we might forget to breathe or to make our hearts beat, and the result would be fatal. In order that the mind may be employed in other concerns, all these matters have been delegated to the medulla oblongata, and we can safely go to sleep without a thought of the question whether our hearts will continue to beat or not.

We may regulate to a certain extent, however, the length of our breath, and may temporarily disturb Interference ^^^ regularity of our heart-beats ; we with the func- ^ decidedly disturb and permanently

tions of medulla •' •' jr -/

oblongata. disarrange the action of our digestive

organs by eating at improper hours, or by habitually forcing those organs to work upon indigestible ''delicacies."

We have found that the power of the mind to act depends upon the condition of the body. If we wish Pr:_« .„„^,>;„„ to have stronsr, active minds, we should

Prime condition o' '

of strong mind. ^^]^q cvcry cffort to kccp the vital organs in a sound, healthy condition.

As an experiment, to show what an effect even a slight change in bodily conditions will have upon the

Experiment, vigor of mental action, the following may be tried. Go out into the open air and walk for fifteen minutes. As you walk, inhale the air slowly while you take six steps, exhaling for the same number of steps. Gradually increase the number of steps for each inhalation and exhalation until you have reached a dozen or fifteen. Lift the arms slowly while inhaling, lowering them while exhaling. Note the effect on the circulation and upon your power to take up your work after the exercise.

What connection do you find between Problem, this experiment and the study of the medulla oblongata.-*

We come now to the brain proper, which consists of two parts, the cerebellutn, or little brain, and the cerebruniy or large brain. The cerebellum is cerebellum, situated in the lower, rear part of the cavity of the skull, and is divided into two hemispheres which envelop the medulla oblongata.

A peculiarity of the cerebellum and cerebrum is found in the arrangement of the substance of which they are composed. Here we find the

Composition of

gray matter on the outside, forming a cerebellum and

cerebrum.

thin coating for the white nerve fibers. This arrangement is rendered safe by the bones of the skull, and it is necessary because the gray matter needs room for growth.

From this arrangement of the nerve matter in the spinal cord and the brain, what inference Problem. do you draw concerning the relative importance of the two kinds }

The function of the cerebellum is to coordinate the action of the muscles. When this part of ^ *• „ ^ .»

^ Function of cer-

the brain is injured the person cannot ^^^^i""^- control his movements. A chicken with the cerebeli6

ESSENTIALS OF PSYCHOLOGY.

lum removed tumbles about with no power of self-direction. Intoxicating liquors seem to affect the cerebellum, and the result is that the person under their influence staggers.

Fig. 4. Diagram (side view) showing arrangement of the cerebrum, cerebellum (A), and medulla {B).

S, fissure of Silvius ; R, fissure of Rolando.

The cerebrum, or large brain, occupies the larger portion of the cranial cavity. Its composition is the

Cerebrum, samc as that of the cerebellum, — an outside covering of gray matter, called the cortex, and an inside mass of connecting white fibers.

It is divided into two hemispheres by a longitudinal fissure, extending from the front to the rear. ^ There are also two large fissures, extending, the Arrangement, one from near the level of the eye backward and upward, called the fissure of Silvius, the other from near the middle of the top of the head downward and toward the front until it almost reaches the' fissure of Silvius. This second fissure is called the fissure of Rolando.

Fig. 5. Showing the principal areas of the left side of the brain.

It will be seen by referring to Fig. 4 that the hemispheres of the brain are divided by these fissures into sections, as indicated. Maps of the brain Brain maps, have been made, and the different physical processes have been referred to their own particular tracts, a general idea of which may be obtained from the diagram, Fig. 5.

It is worth while to notice, however, that no one has yet been able to locate the place where the mind really Maps unsatis. i^, whcrc the thinking, remembering, feelfactory. jj^g^ ^^ j willing take place. That is to say,

no one is as yet able to tell me just what part of the brain the / really occupies as headquarters.

The most interesting part of the brain is the cortex. Cortex. which is composed of nerve cells estimated to vary in number from five hundred millions to two billions.

Recent investigations have brought to light some

very interesting facts about nerve cells. If you plant

a dozen peas in moist, shallow earth and

Nerve cells and

their develop- place them in a sunny window and dig

ment.

up one each day, observing carefully what has taken place, you will have very well illustrated what takes place in a nerve cell as we start it into action by a sense impression and then keep it active by memory, thought, etc. The result of these investigations seems to show that brain cells may be developed almost indefinitely while the brain is in a plastic condition. As they develop they keep putting out roots upon which their strength seems to depend, just as the strength of a plant lies in its roots.

Problem. What would naturally be the conditions under which brain cells might be developed ?

In infancy the cortex conforms to the shape of the skull. As the nerve cells develop, and their roots increase in number and size, more room ^^^^^ deveiopis needed. The consequence is that the ^^^^' nerve cells, by crowding one another, push the cortex out of shape, and its surface becomes seamed and convoluted. This process of brain evolution may be carried on till the brain ceases to be plastic, a time which anatomists place at from twenty-five to thirty-five years.

If this is true, what effect should the Problem, knowledge of it have upon us as students ? Why }

After the growth of the brain ceases, we are told, we are practically incapable of taking up any absolutely new line of work. Our brains have Limitations of formed their habits of working, good or "^^"'^ power, bad, and refuse to work in new ways. A few years ago the discoveries of scientists made it plain that this earth of ours is far older than six thousand years, and that it was many centuries in the building. The people who had always been accustomed to accept the figures of early Bible students as a part of the Bible itself, and the first chapter of Genesis as literal history, could not bring themselves to accept the truth, because their brains refused to work along the new lines.

Not only do we become incapable of appropriating to our use new lines of thought, but we must also keep exercising our minds along the old lines unless

we wish to lose the power of using them, for the

brain, iust as the body, will lose power

Need of constant mental by disuse. We know that if we carry

exercise.

one arm in a sling it soon becomes weaker than the other, and that it will eventually lose all power unless exercised. So the brain needs exercise to develop or maintain its vigor.

Connected with these higher nerve centers is the peripheral system, nerves having their ramifications

over the whole body, ending at the surface

Peripheral system and its of the body, serving to set in motion the

value.

communication between the outside world and the brain. If we possessed the central system without the peripheral system, we could gain no knowledge of what is going on outside. It is this peripheral system, then, that we want to study most carefully.

If the central system is in a healthy condition, it is our business to see to it that it has an abundance of Need and material to work upon. This we can do

method of fur- ^ cultivating and educating the different

nishing the mind jo o

with materials, gj^j ncrvcs of the peripheral system, or, as we generally call them, the five senses. If the five senses are all the time on the alert for raw material, we are all the time accumulating knowledge.

In this connection, can you give any good reason for the existence of the Kindergarten ? Of what practical value are the games and stories and songs? Problems. In the common-school system, what is the value of drawing, of modeling, and of music ?

Let us now inquire how the connection is made between the outside world, the world of matter, and the inside world, the world of mind. When ^^^^^^ ^^ ^^^. you touch your finp-er to any substance, mumcation be-

-' J o J ' tween mind and

as, for example, the point of a needle, a n^a"er. highly interesting process is set in motion. The needle point irritated the end of a sensory nerve. This irritation was telegraphed, in the form of a vibration, along the nerve fiber to the brain, where it reached its proper nerve cell. There, in some mysterious way, this impression, or vibration, was transformed into a sejisatiouy the character of which was determined by the character of the touch : if the touch was light, the sensation was a tickling sensation ; if hard, a painful sensation. The mind, seizing upon and interpreting this sensation, immediately sent a message to the finger-tip along the motor nerve, the companion to the sensory nerve affected, telling the finger to move away from the needle.

In the case of the lower extremities the impression may not always be carried to the brain, and we have what is called reflex action. It seems that the brain delegates some small portion of its directive power to the lower centers, always, however, with the reserva- Reflex action, tlon that the brain may assume active control at any time. This is the reason why, when you have started out for a walk, it is not necessary that you should take care to direct every step. You set the body in motion and then turn your mind to anything you please. You converse with your friends, you listen to the singing of the birds, or look at the flowers and trees, and yet you are walking all the time, the movements being kept up by the reflex action of the nerve centers in the spinal cord.