In this little book I have endeavoured to maintain the simplicity which is the ideal of this series. It is more difficult, however, to be simple in a topic which, even in its illustrations, demands of the reader more or less facility in the exploration of his own mind. I am persuaded that the attempt to make the matter of psychology more elementary than is here done, would only result in making it untrue and so in defeating its own object.
In preparing the book I have secured the right and welcomed the opportunity to include certain more popular passages from earlier books and articles. It is necessary to say this, for some people are loath to see a man repeat himself. When one has once said a thing, however, about as well as he can say it, there is no good reason that he should be forced into the pretence of saying something different simply to avoid using the same form of words a second time. The question, of course, is as to whether he should not then resign himself to keeping still, and letting others do the further speaking. There is much to be said for such a course. But if one have the right to print more severe and difficult things, and think he really has something to say which would instruct the larger audience, it would seem only fair to allow him to speak in the simpler way also, even though all that he says may not have the merit of escaping the charge of infringing his own copyrights!
I am indebted to the proprietors of the following magazines for the use of such passages: The Popular Science Monthly, The Century Magazine, The Inland Educator; and with them I also wish to thank The Macmillan Company and the owners of Appletons' Universal Cyclopædia.
As to the scope and contents of the Story, I have aimed to include enough statement of methods and results in each of the great departments of psychological research to give the reader an intelligent idea of what is being done, and to whet his appetite for more detailed information. In the choice of materials I have relied frankly on my own experience and in debatable matters given my own opinions. This gives greater reality to the several topics, besides making it possible, by this general statement, at once to acknowledge it, and also to avoid discussion and citation of authorities in the text. At the same time, in the exposition of general principles I have endeavoured to keep well within the accepted truth and terminology of psychology.
It will be remarked that in several passages the evolution theory is adopted in its application to the mind. While this great theory can not be discussed in these pages, yet I may say that, in my opinion, the evidence in favour of it is about the same, and about as strong, as in biology, where it is now made a presupposition of scientific explanation. So far from being unwelcome, I find it in psychology no less than in biology a great gain, both from the point of view of scientific knowledge and from that of philosophical theory. Every great law that is added to our store adds also to our conviction that the universe is run through with Mind. Even so-called Chance, which used to be the "bogie" behind Natural Selection, has now been found to illustrate—in the law of Probabilities—the absence of Chance. As Professor Pearson has said: "We recognise that our conception of Chance is now utterly different from that of yore.... What we are to understand by a chance distribution is one in accordance with law, and one the nature of which can, for all practical purposes, be closely predicted." If the universe be pregnant with purpose, as we all wish to believe, why should not this purpose work itself out by an evolution process under law?—and if under law, why not the law of Probabilities? We who have our lives insured provide for our children through our knowledge and use of this law; and our plans for their welfare, in most of the affairs of life, are based upon the recognition of it. Who will deny to the Great Purpose a similar resource in producing the universe and in providing for us all?
I add in a concluding section on Literature some references to various books in English, classified under the headings of the chapters of the text. These works will further enlighten the reader, and, if he persevere, possibly make a psychologist of him.
J. Mark Baldwin.
Princeton, April, 1898.
| FIGURE | PAGE | |
| 1. | Origin of instinct by organic selection | 35 |
| 2. | Reflex and voluntary circuits | 107 |
| 3. | Outer surface of the left hemisphere of the brain | 110 |
| 4. | Inner surface or the right hemisphere of the brain | 111 |
| 5. | The speech zone (after Collins) | 113 |
| 6. | Mouth-key | 131 |
| 7. | Apparatus for optical experiment | 135 |
| 8. | Memory curves | 140 |
Psychology is the science of the mind. It aims to find out all about the mind—the whole story—just as the other sciences aim to find out all about the subjects of which they treat—astronomy, of the stars; geology, of the earth; physiology, of the body. And when we wish to trace out the story of the mind, as psychology has done it, we find that there are certain general truths with which we should first acquaint ourselves; truths which the science has been a very long time finding out, but which we can now realize without a great deal of explanation. These general truths, we may say, are preliminary to the story itself; they deal rather with the need of defining, first of all, the subject or topic of which the story is to be told.
1. The first such truth is that the mind is not the possession of man alone. Other creatures have minds. Psychology no longer confines itself, as it formerly did, to the human soul, denying to the animals a place in this highest of all the sciences. It finds itself unable to require any test or evidence of the presence of mind which the animals do not meet, nor does it find any place at which the story of the mind can begin higher up than the very beginnings of life. For as soon as we ask, "How much mind is necessary to start with?" we have to answer, "Any mind at all"; and all the animals are possessed of some of the actions which we associate with mind. Of course, the ascertainment of the truth of this belongs—as the ascertainment of all the truths of nature belongs—to scientific investigation itself. It is the scientific man's rule not to assume anything except as he finds facts to support the assumption. So we find a great department of psychology devoted to just this question—i.e., of tracing mind in the animals and in the child, and noting the stages of what is called its "evolution" in the ascending scale of animal life, and its "development" in the rapid growth which every child goes through in the nursery. This gives us two chapters of the story of the mind. Together they are called "Genetic Psychology," having two divisions, "Animal or Comparative Psychology" and "Child Psychology."
2. Another general truth to note at the outset is this: that we are able to get real knowledge about the mind. This may seem at first sight a useless question to raise, seeing that our minds are, in the thought of many, about the only things we are really sure of. But that sort of sureness is not what science seeks. Every science requires some means of investigation, some method of procedure, which is more exact than the mere say-so of common sense; and which can be used over and again by different investigators and under different conditions. This gives a high degree of verification and control to the results once obtained. The chemist has his acids, and reagents, and blowpipes, etc.; they constitute his instruments, and by using them, under certain constant rules, he keeps to a consistent method. So with the physiologist; he has his microscope, his staining fluids, his means of stimulating the tissues of the body, etc. The physicist also makes much of his lenses, and membranes, and electrical batteries, and X-ray apparatus. In like manner it is necessary that the psychologist should have a recognised way of investigating the mind, which he can lay before anybody saying: "There, you see my results, you can get them for yourself by the same method that I used."
In fulfilling this requirement the psychologist resorts to two methods of procedure. He is able to investigate the mind in two ways, which are of such general application that anybody of sufficient training to make scientific observations at all can repeat them and so confirm the results. One of these is what is called Introspection. It consists in taking note of one's own mind, as all sorts of changes are produced in it, such as emotions, memories, associations of events now gone, etc., and describing everything that takes place. Other persons can repeat the observations with their own minds, and see that what the first reports is true. This results in a body of knowledge which is put together and called "Introspective Psychology," and one chapter of the story should be devoted to that.
Then the other way we have is that of experimenting on some one else's mind. We can act on our friends and neighbours in various ways, making them feel, think, accept, refuse this and that, and then observe how they act. The differences in their action will show the differences in the feelings, etc., which we have produced. In pursuing this method the psychologist takes a person—called the "subject" or the "re-agent"—into his laboratory, asks him to be willing to follow certain directions carefully, such as holding an electric handle, blowing into a tube, pushing a button, etc., when he feels, sees, or hears certain things; this done with sufficient care, the results are found recorded in certain ways which the psychologist has arranged beforehand. This second way of proceeding gives results which are gathered under the two headings "Experimental" and "Physiological Psychology." They should also have chapters in our story.
3. There is besides another truth which the psychologist nowadays finds very fruitful for his knowledge of the mind; this is the fact that minds vary much in different individuals, or classes of individuals. First, there is the pronounced difference between healthy minds and diseased minds. The differences are so great that we have to pursue practically different methods of treating the diseased, not only as a class apart from the well minds—putting such diseased persons into institutions—but also as differing from one another. Just as the different forms of bodily disease teach us a great deal about the body—its degree of strength, its forms of organization and function, its limitations, its heredity, the inter-connection of its parts, etc.—so mental diseases teach us much about the normal mind. This gives another sphere of information which constitutes "Abnormal Psychology" or "Mental Pathology."
There are also very striking variations between individuals even within normal life; well people are very different from one another. All that is commonly meant by character or temperament as distinguishing one person from another is evidence of these differences. But really to know all about mind we should see what its variations are, and endeavour to find out why the variations exist. This gives, then, another topic, "Individual or Variational Psychology." This subject should also have notice in the story.
4. Allied with this the demand is made upon the psychologist that he show to the teacher how to train the mind; how to secure its development in the individual most healthfully and productively, and with it all in a way to allow the variations of endowment which individuals show each to bear its ripest fruit. This is "Educational or Pedagogical Psychology."
5. Besides all these great undertakings of the psychologist, there is another department of fact which he must some time find very fruitful, although as yet he has not been able to investigate it thoroughly: he should ask about the place of the mind in the world at large. If we seek to know what the mind has done in the world, what a wealth of story comes to us from the very beginnings of history! Mind has done all that has been done: it has built human institutions, indited literature, made science, discovered the laws of Nature, used the forces of the material world, embodied itself in all the monuments which stand to testify to the presence of man. What could tell us more of what mind is than this record of what mind has done? The ethnologists are patiently tracing the records left by early man in his utensils, weapons, clothing, religious rites, architectural remains, etc., and the anthropologists are seeking to distinguish the general and essential from the accidental and temporary in all the history of culture and civilization. They are making progress very slowly, and it is only here and there that principles are being discovered which reveal to the psychologist the necessary modes of action and development of the mind. All this comes under the head of "Race Psychology."
6. Finally, another department, the newest of all, investigates the action of minds when they are thrown together in crowds. The animals herd, the insects swarm, most creatures live in companies; they are gregarious, and man no less is social in his nature. So there is a psychology of herds, crowds, mobs, etc., all put under the heading of "Social Psychology." It asks the question, What new phases of the mind do we find when individuals unite in common action?—or, on the other hand, when they are artificially separated?
We now have with all this a fairly complete idea of what The Story of the Mind should include, when it is all told. Many men are spending their lives each at one or two of these great questions. But it is only as the results are all brought together in a consistent view of that wonderful thing, the mind, that we may hope to find out all that it is. We must think of it as a growing, developing thing, showing its stages of evolution in the ascending animal scale, and also in the unfolding of the child; as revealing its nature in every change of our daily lives which we experience and tell to one another or find ourselves unable to tell; as allowing itself to be discovered in the laboratory, and as willing to leave the marks of its activity on the scientist's blackened drum and the dial of the chronoscope; as subject to the limitations of health and disease, needing to be handled with all the resources of the asylum, the reformatory, the jail, as well as with the delicacy needed to rear the sensitive girl or to win the love of the bashful maid; as manifesting itself in the development of humanity from the first rude contrivances for the use of fire, the first organizations for defence, and the first inscriptions of picture writing, up to the modern inventions in electricity, the complex constitutions of government, and the classic productions of literary art; and as revealing its possibilities finally in the brutal acts of the mob, the crimes of a lynching party, and the deeds of collective righteousness performed by our humane and religious societies.
It would be impossible, of course, within the limits of this little volume, to give even the main results in so many great chapters of this ambitious and growing science. I shall not attempt that; but the rather select from the various departments certain outstanding results and principles. From these as elevations the reader may see the mountains on the horizon, so to speak, which at his leisure, and with better guides, he may explore. The choice of materials from so rich a store has depended also, as the preface states, on the writer's individual judgment, and it is quite probable that no one will find the matters altogether wisely chosen. All the great departments now thus briefly described, however, are represented in the following chapters.
Of all the sources now indicated from which the psychologist may draw, that of so-called Introspective Psychology—the actual reports of what we find going on in our minds from time to time—is the most important. This is true for two great reasons, which make Psychology different from all the other sciences. The first claim which the introspective method has upon us arises from the fact that it is only by it that we can examine the mind directly, and get its events in their purity. Each of us knows himself better than he knows any one else. So this department, in which we deal each with his own consciousness at first hand, is more reliable, if free from error, than any of those spheres in which we examine other persons, so long as we are dealing with the psychology of the individual. The second reason that this method of procedure is most important is found in the fact that all the other departments of psychology—and with them all the other sciences—have to use introspection, after all, to make sure of the results which they get by other methods. For example, the natural scientist, the botanist, let us say, and the physical scientist, the electrician, say, can not observe the plants or the electric sparks without really using his introspection upon what is before him. The light from the plant has to go into his brain and leave a certain effect in his mind, and then he has to use introspection to report what he sees. The astronomer who has bad eyes can not observe the stars well or discover the facts about them, because his introspection in reporting what he sees proceeds on the imperfect and distorted images coming in from his defective eyesight. So a man given to exaggeration, who is not able to report truthfully what he remembers, can not be a good botanist, since this defect in introspection will render his observation of the plants unreliable.
In practice the introspective method has been most important, and the development of psychology has been up to very recently mainly due to its use. As a consequence, there are many general principles of mental action and many laws of mental growth already discovered which should in the first instance engage our attention. They constitute the main framework of the building; and we should master them well before we go on to find the various applications which they have in the other departments of the subject.
The greater results of "Introspective" or, as it is very often called, "General" psychology may be summed up in a few leading principles, which sound more or less abstract and difficult, but which will have many concrete illustrations in the subsequent chapters. The facts of experience, the actual events which we find taking place in our minds, fall naturally into certain great divisions. These are very easily distinguished from one another. The first distinction is covered by the popularly recognised difference between "thought and conduct," or "knowledge and life." On the one hand, the mind is looked at as receiving, taking in, learning; and on the other hand, as acting, willing, doing this or that. Another great distinction contrasts a third mental condition, "feeling," with both of the other two. We say a man has knowledge, but little feeling, head but no heart; or that he knows and feels the right but does not live up to it.
I. On the side of Reception we may first point out the avenues through which our experiences come to us: these are the senses—a great number, not simply the five special senses of which we were taught in our childhood. Besides Sight, Hearing, Taste, Smell, and Touch, we now know of certain others very definitely. There are Muscle sensations coming from the moving of our limbs, Organic sensations from the inner vital organs, Heat and Cold sensations which are no doubt distinct from each other, Pain sensations probably having their own physical apparatus, sensations from the Joints, sensations of Pressure, of Equilibrium of the body, and a host of peculiar sensational conditions which, for all we know, may be separate and distinct, or may arise from combinations of some of the others. Such, for example, are the sensations which are felt when a current of electricity is sent through the arm.
All these give the mind its material to work upon; and it gets no material in the first instance from any other source. All the things we know, all our opinions, knowledges, beliefs, are absolutely dependent at the start upon this supply of material from our senses; although, as we shall see, the mind gets a long way from its first subjection to this avalanche of sensations which come constantly pouring in upon it from the external world. Yet this is the essential and capital function of Sensation: to supply the material on which the mind does the work in its subsequent thought and action.
Next comes the process by which the mind holds its material for future use, the process of Memory; and with it the process by which it combines its material together in various useful forms, making up things and persons out of the material which has been received and remembered—called Association of Ideas, Thinking, Reasoning, etc. All these processes used to be considered as separate "faculties" of the soul and as showing the mind doing different things. But that view is now completely given up. Psychology now treats the activity of the mind in a much more simple way. It says: Mind does only one thing; in all these so-called faculties we have the mind doing this one thing only on the different materials which come and go in it. This one thing is the combining, or holding together, of the elements which first come to it as sensations, so that it can act on a group of them as if they were only one and represented only one external thing. Let me illustrate this single and peculiar sort of process as it goes on in the mind.
We may ask how the child apprehends an orange out there on the table before him. It can not be said that the orange goes into the child's mind by any one of its senses. By sight he gets only the colour and shape of the orange, by smell he gets only its odour, by taste its sweetness, and by touch its smoothness, rotundity, etc. Furthermore, by none of these senses does he find out the individuality of the orange, or distinguish it from other things which involve the same or similar sensations—say an apple. It is easy to see that after each of the senses has sent in its report something more is necessary: the combining of them all together in the same place and at the same time, the bringing up of an appropriate name, and with that a sort of relating or distinguishing of this group of sensations from those of the apple. Only then can we say that the knowledge, "here is an orange," has been reached. Now this is the one typical way the mind has of acting, this combining of all the items or groups of items into ever larger and more fruitful combinations. This is called Apperception. The mind, we say, "apperceives" the orange when it is able to treat all the separate sensations together as standing for one thing. And the various circumstances under which the mind does this give the occasions for the different names which the earlier psychology used for marking off different "faculties."
These names are still convenient, however, and it may serve to make the subject clear, as well as to inform the reader of the meaning of these terms, to show how they all refer to this one kind of mental action.
The case of the orange illustrates what is usually called Perception. It is the case in which the result is the knowledge of an actual object in the outside world. When the same process goes on after the actual object has been removed it is Memory. When it goes on again in a way which is not controlled by reference to such an outside object—usually it is a little fantastic, as in dreams or fancy, but often it is useful as being so well done as to anticipate what is really true in the outside world—then it is Imagination. If it is actually untrue, but still believed in, we call it Illusion or Hallucination. When it uses mere symbols, such as words, gestures, writing, etc., to stand for whole groups of things, it is Thinking or Reasoning. So we may say that what the mind arrives at through this its one great way of acting, no matter which of these forms it takes on, except in the cases in which it is not true in its results to the realities, is Knowledge.
Thus we see that the terms and faculties of the older psychology can be arranged under this doctrine of Apperception without the necessity of thinking of the mind as doing more than the one thing. It simply groups and combines its material in different ways and in ever higher degrees of complexity.
Apperception, then, is the one principle of mental activity on the side of its reception and treatment of the materials of experience.
There is another term very current in psychology by which this same process is sometimes indicated: the phrase Association of Ideas. This designates the fact that when two things have been perceived or thought of together, they tend to come up together in the mind in the future; and when a thing has been perceived which resembles another, or is contrasted with it, they tend to recall each other in the same way. It is plain, however, that this phrase is applied to the single thoughts, sensations, or other mental materials, in their relations or connections among themselves. They are said to be "associated" with one another. This way of speaking of the mental materials, instead of speaking of the mind's activity, is convenient; and it is quite right to do so, since it is no contradiction to say that the thoughts, etc., which the mind "apperceives" remain "associated" together. From this explanation it is evident that the Association of Ideas also comes under the mental process of Apperception of which we have been speaking.
There is, however, another tendency of the mind in the treatment of its material, a tendency which shows us in actual operation the activity with which we have now become familiar. When we come to look at any particular case of apperception or association we find that the process must go on from the platform which the mind's attainments have already reached. The passing of the mental states has been likened to a stream which flows on from moment to moment with no breaks. It is so continuous that we can never say: "I will start afresh, forget the past, and be uninfluenced by my history." However we may wish this, we can never do it; for the oncoming current of the stream is just what we speak of as ourselves, and we can not avoid bringing the memories, imaginations, expectations, disappointments, etc., up to the present. So the effect which any new event or experience, happening for the first time, is to have upon us depends upon the way it fits into the current of these onflowing influences. The man I see for the first time may be so neutral to me that I pass him unregarded. But let him return after I have once remarked him, or let him resemble a man whom I know, or let him give me some reason to observe, fear, revere, think of him in any way, then he is a positive factor in my stream. He has been taken up into the flow of my mental life, and he henceforth contributes something to it.
For example, a little child, after learning to draw a man's face, with two eyes, the nose and mouth, and one ear on each side, will afterward, when told to draw a profile, still put in two eyes and affix an ear to each side. The drift of mental habit tells on the new result and he can not escape it.
He will still put in the two eyes and two ears when he has before him a copy showing only one ear and neither eye.
In all such cases the new is said to be Assimilated to the old. The customary figure for man in the child's memory assimilates the materials of the new copy set before him.
Now this tendency is universal. The mind must assimilate its new material as much as possible, thus making the old stand for the new. Otherwise there would be no containing the fragmentary details which we should have to remember and handle. Furthermore, it is through this tendency that we go on to form the great classes of objects—such as man, animal, virtue—into which numbers of similar details are put, and which we call General Notions or Concepts.
We may understand by Assimilation, therefore, the general tendency of new experiences to be treated by us in the ways which similar material has been treated before, with the result that the mind proceeds from the particular case to the general class.
Summing up our outcome so far, we find that general psychology has reached three great principles in its investigation of knowledge. First, we have the combining tendency of the mind, the grouping together and relating of mental states and of things, called Apperception. Then, second, there are the particular relations established among the various states, etc., which are combined; these are called Associations of Ideas. And, third, there is the tendency of the mind to use its old experiences and habits as general patterns or nets for the sorting out and distributing of all the new details of daily life; this is called Assimilation.
II. Let us now turn to the second great aspect of the mind, as general or introspective psychology considers it, the aspect which presents itself in Action or conduct. The fact that we act is of course as important as the fact that we think or the fact that we feel; and the distinction which separates thought and action should not be made too sharp.
Yet there is a distinction. To understand action we must again go to introspection. This comes out as soon as we ask how we reach our knowledge of the actions of others. Of course, we say at once that we see them. And that is true; we do see them, while as to their thoughts we only infer them from what we see of their action. But, on the other hand, we may ask: How do we come to infer this or that thought from this or that action of another? The only reply is: Because when we act in the same way this is the way we feel. So we get back in any case to our own consciousness and must ask how is this action related to this thought in our own mind.
To this question psychology has now a general answer: Our action is always the result of our thought, of the elements of knowledge which are at the time present in the mind. Of course, there are actions which we do from purely nervous reasons. These are the Instincts, which come up again when we consider the animals. But these we may neglect so long as we are investigating actions which we consider our own. Apart from the Instincts, the principle holds that behind every action which our conduct shows there must be something thought of, some sensation or knowledge then in mind, some feeling swelling within our breast, which prompts to the action.
This general principle is Motor Suggestion. It simply means that we are unable to have any thought or feeling whatever, whether it comes from the senses, from memory, from the words, conduct, or command of others, which does not have a direct influence upon our conduct. We are quite unable to avoid the influence of our own thoughts upon our conduct, and often the most trivial occurrences of our daily lives act as suggestions to deeds of very great importance to ourselves and others. For example, the influence of the newspaper reports of crime stimulate other individuals to perform the same crimes by this principle of suggestion; for the fact is that the reading of the report causes us to entertain the thoughts, and these thoughts tend to arouse in us their corresponding trains of suggested action.
The most interesting and striking sphere of operation of the principle of Suggestion (of other sorts as well as motor) is what is commonly known simply as Hypnotism. To that, as well as to further illustrations of Suggestion, we will return later on.
We are able, however, to see a little more in detail how the law of Motor Suggestion works by asking what sort of action is prompted in each case of thought or feeling, at the different levels of the mind's activity which have been distinguished above as all illustrating Apperception—e.g., the stages known as Perception, Imagination, Reasoning, etc.
We act, of course, on our perceptions constantly; most of our routine life is made up of such action on the perceptions of objects which lie about us. The positions of things in the house, in the streets, in the office, in the store, are so well known that we carry out a series of actions with reference to these objects without much supervision from our consciousness. Here the law of Motor Suggestion works along under the guidance of Perception, Memory, and the Association of Ideas. Then we find also, in much of our action, an element due to the exercise of the Imagination. We fill in the gaps in the world of perception by imagining appropriate connections; and we then act as if we knew that these imaginations were realities. This is especially true in our intercourse with our fellow-men. We never really know what they will do from time to time. Their action is still future and uncertain; but from our familiarity with their character, we surmise or imagine what they expect or think, and we then act so as to make our conduct fit into theirs. Here is suggestion of a personal kind which depends upon our ability, in a sense, to reconstruct the character of others, leading us out into appropriate action. This is the sphere of the most important affairs of our lives. It appears especially so when we consider its connection with the next great sort of action from suggestion.
This next and highest sphere is action from the general or abstract thoughts which we have been able to work up by the apperceiving activity of the mind. In this sphere we have a special name for those thoughts which influence us directly and lead us to action: we call such thoughts Motives. We also have a special name for the sort of action which is prompted by clearly-thought-out motives: Will. But in spite of this emphasis given to certain actions of ours as springing from what is called Will, we must be careful to see that Will is not a new faculty, or capacity, added to mind, and which is different from the ways of action which the mind had before the Will arose. Will is only a name for the action upon suggestions of conduct which are so clear in our minds that we are able to deliberate upon them, acting only after some reflection, and so having a sense that the action springs from our own choice. The real reasons for action, however, are thoughts, in this case, just as in the earlier cases they were. In this case we call them Motives; but we are dependent upon these Motives, these Suggestions; we can not act without Motives, nor can we fail to act on those Motives which we have; just as, in the earlier cases, we could not act without some sort of Perceptions or Imaginations or Memories, and we could not fail to act on the Perceptions or other mental states which we had. Voluntary action or Will is therefore only a complex and very highly conscious case of the general law of Motor Suggestion; it is the form which suggested action takes on when Apperception is at its highest level.
The converse of Suggestion is also true—that we can not perform an action without having in the mind at the time the appropriate thought, or image, or memory to suggest the action. This dependence of action upon the thought which the mind has at the time is conclusively shown in certain patients having partial paralysis. These patients find that when the eyes are bandaged they can not use their limbs, and it is simply because they can not realize without seeing the limb how it would feel to move it; but open the eyes and let them see the limb—then they move it freely. A patient can not speak when the cortex of the brain is injured in the particular spot which is used in remembering how the words feel or sound when articulated. Many such cases lead to the general position that for each of our intentional actions we must have some way of thinking about the action, of remembering how it feels, looks, etc.; we must have something in mind equivalent to the experience of the movement. This is called the principle of Kinæsthetic Equivalents, an expression which loses its formidable sound when we remember that "kinæsthetic" means having the feeling of movement; so the principle expresses the truth that we must in every case have some thought or mental picture in mind which is equivalent to the feeling of the movement we desire to make; if not, we can not succeed in making it.
What we mean by the "freedom" of the will is not ability to do anything without thinking, but ability to think all the alternatives together and to act on this larger thought. Free action is the fullest expression of thought and of the Self which thinks it.
It is interesting to observe the child getting his Equivalents day by day. He can not perform a new movement simply by wishing to do so; he has no Equivalents in his mind to proceed upon. But as he learns the action, gradually striking the proper movements one by one—oftenest by imitation, as we will see later on—he stores the necessary Equivalents up in his memory, and afterward only needs to think how the movements feel or look, or how words sound, to be able to make the movements or speak the words forthwith.