The Learning of Complex Practical Performances

A great deal of light has been thrown on the learning process by psychological studies of the course of improvement in mastering such trades as telegraphy and typewriting.

A student of telegraphy was tested once a week to see how rapidly he could send a message, and also how rapidly he could "receive a message off the wire", by listening to the clicking of the sounder. The number of letters sent or received per minute was taken as the measure of his proficiency. This number increased rapidly in the first few weeks, and then more and more slowly, giving a typical learning curve, or "practice curve", as it is also called.

The receiving {322} curve rose more slowly than the sending curve, and flattened out after about four months of practice, showing little further improvement for the next two months. This was a discouraging time for the student, for it seemed as if he could never come up to the commercial standard. In fact, many learners drop out at this stage. But this student persisted, and, after the long period of little improvement, was gratified to find his curve going up rapidly again. It went up rapidly for several months, and when it once more tapered off into a level, he was well above the minimum standard for regular employment.

Such a flat stretch in a practice curve, followed by a second rise--such a period of little or no improvement, followed by rapid improvement--is called a "plateau". Sometimes due to mere discouragement, or to the inattention that naturally supervenes when an act becomes easy to perform, it often has a different cause. It may, in fact, represent a true physiological limit for the act as it is being performed, and the subsequent rise to a higher level may result from improved methods of work. That was probably the case with the telegrapher.

[Footnote: A plateau of this sort is present in the learning curve for mastery of a puzzle, given on p. 316.]

The telegrapher acquires skill by improving his methods, rather than by simply speeding up. He acquires methods that he didn't dream of at first. At the start, he must learn the alphabet of dots and dashes. This means, for purposes of sending, that he must learn the little rhythmical pattern of finger movements that stands for each letter; and, for purposes of receiving, that he must learn the rhythmical {323} pattern of clicks from the sounder that stands for a letter. When he has learned the alphabet, he is able to send and receive slowly. In sending, he spells out the words, writing each letter as a separate act. In receiving, at this early stage, he must pick out each separate letter from the continuous series of clicks that he hears from the sounder. By degrees, the letters become so familiar that he goes through this spelling process easily; and, doing now so much better than at the outset, he supposes he has learned the trade, in its elements, and needs only to put on more speed.

But not at all! He has acquired but a small part of the necessary stock-in-trade of the telegrapher. He has his "letter habits", but knows nothing as yet of "word habits". These gradually come to him as he continues his practice. He comes to know words as units, motor units for sending purposes, auditory units for receiving. The rhythmical pattern of the whole word becomes a familiar unit. Short, much used words are first dealt with as units, then more and more words, till he has a large vocabulary of word habits. A word that has become a habit need not be spelled out in sending, nor laboriously dug out letter by letter in receiving; you simply think the word "train", and your finger taps it out as a connected unit; or, in receiving, you recognize the characteristic pattern of this whole series of clicks. When the telegrapher has reached this word habit stage, he finds the new method far superior, in both speed and sureness, to the letter habit method which he formerly assumed to be the whole art of telegraphy. He does not even stop with word habits, but acquires a similar control over familiar phrases.

Higher Units and Overlapping

The acquisition of skill in telegraphy consists mostly in learning these higher units of reactions. It is the same in {324} learning to typewrite. First you must learn your alphabet of letter-striking movements; by degrees you reduce these finger movements to firm habits, and are then in the letter-habit stage, in which you spell out each word as you write it. After a time, you write a familiar word without spelling it, by a coördinated series of finger movements; you write by word units, and later, in part, by phrase units; and these higher units give you speed and accuracy.

Along with this increase in the size of the reaction-units employed goes another factor of skill that is really very remarkable. This is the "overlapping" of different reactions, a species of doing two or more things at once, only that the two or more reactions are really parts of the same total activity. The simplest sort of overlap can be illustrated at an early stage in learning to typewrite. The absolute beginner at the typewriter, in writing "and", pauses after each letter to get his bearings before starting on the next; but after a small amount of practice he will locate the second letter on the keyboard while his finger is still in the act of striking the first letter. Thus the sensory part of the reaction to the second letter commences before the motor part of reacting to the first letter is finished; and this overlap does away with pauses between letters and makes the writing smoother and more rapid.

With further practice in typewriting, when word habits and phrase habits are acquired, overlap goes to much greater lengths. One expert kept her eyes on the copy about four words ahead of her fingers on the keyboard, and thus was reacting to about four words at the same time: one word was just being read from the copy, one word was being written, and the two words between were being organized and prepared for actual writing. The human typewriting mechanism, consisting of eye, optic nerve, parts of the brain and cord, motor nerves and muscles, works somewhat like one of {325} those elaborate machines which receive raw material steadily at one end perform a series of operations upon it, and keep turning out finished product at the other end.

All this is very remarkable, but the same sort of overlapping and working with large units can be duplicated in many linguistic performances that every one makes. In reading aloud, the eyes keep well ahead of the voice, and seeing, understanding and pronouncing are all applied simultaneously to different words of the passage read. In talking, the ideas keep developing and the spoken words tag along behind.

In telegraphy and typewriting, it is almost inevitable that the learner should start with the alphabet and proceed to gradually larger units. But in learning to talk, or to read, the process goes the other way. The child understands spoken words and phrases before breaking them up into their elementary vocal sounds; and he can better be taught to read by beginning with whole words, or even with whole {326} sentences, than by first learning the alphabet and laboriously spelling out the words. In short, the learning process often takes its start with the higher units, and reaches the smaller elements only for the purpose of more precise control.

Moderate Skill Acquired in the Ordinary Day's Work

Merely repeating a performance many times does not give the high degree of skill that we see in the expert telegrapher or typist. Ordinarily, we practise much less assiduously, are much less zealous, and have no such perfect measure of the success of our work. For "practice to make perfect", it must be strongly motivated, and it must be sharply checked up by some index or measure of success or failure. If the success of a performance can be measured, and chalked up before the learner's eyes in the form of a practice curve, so that he can see his progress, this acts as a strong incentive to rapid improvement.

Ordinarily, we have no clear indication of exactly how well we are doing, and are satisfied if we get through our job easily and without too much criticism and ridicule from people around. Consequently we reach only a moderate degree of skill, nowhere near the physiological limit, and do not acquire the methods of the real expert.

This is very true of the manual worker. Typesetters of ten or more years' experience were once selected as subjects for an experiment on the effects of alcohol, because it was assumed that they must have already reached their maximum skill. In regard to alcohol, the result was that this drug caused a falling off in speed and accuracy of work--but that is another story. What we are interested in here is the fact that, as soon as these long-practised operators found themselves under observation, and their work measured, they all began to improve and in the course of a couple of weeks {327} reached quite a new level of performance. Their former level had been reasonably satisfactory under workaday conditions, and special incentive was needed to make them approach their limit.

A similar condition of affairs has been disclosed by "motion studies" in many kinds of manual work; the movements of the operative have been photographed or closely examined by the efficiency expert, and analyzed to determine whether there are any superfluous movements that could be eliminated, and whether a different method of work would be economical of time and effort. Usually, superfluous motion has been found and considerable economy seen to be possible. There is evidently no law of learning to the effect that continued repetition of a performance necessarily makes it perfect in speed, ease, or adaptation to the task in hand. What the manual worker attains as the result of prolonged experience is a passable performance, but not at all the maximum of skill.

The brain worker has little to brag of as against the manual worker. He, too, is only moderately efficient in doing his particular job. There are brilliant exceptions--bookkeepers who add columns of figures with great speed and precision, students who know just how to put in two hours of study on a lesson with the maximum of effect, writers who always say just what they wish to say and hit the nail on the head every time--but the great majority of us are only passable. We need strong incentive, we need a clear and visible measure of success or failure, we need, if such a thing were possible, a practice curve before us to indicate where we stand at the present moment with respect to our past and our possible future.

Habit

A habit is contrasted with a reflex, in that the reflex is native, the habit acquired; but both are alike in being prompt and automatic reactions. The best antithesis to a habit is the response of a person to a novel situation, where neither nature nor previous experience gives him a ready response. The new response is exploratory and tentative, while habit is fixed and definite. The new response is variable, the habit regular. The new response is slow and uncertain, the habit fairly quick and accurate. The new response is attended by effort and strained attention, the habit is easy and often only half-conscious. The new response is apt to be unsatisfying to the one who makes it, while habit is comfortable and a source of satisfaction.

To break a habit is most uncomfortable. Nature--at least that "second nature" which is habit--calls aloud for the customary performance. Strenuous effort is required to get out of the rut, and the slipping back into the rut which is almost sure to occur in moments of inadvertence is humiliating. Result--usually the habit sticks.

But if the habit simply must be broken? Breaking a habit is forming a counter-habit, and the more positive the counter-habit the better for us. This counter-habit must not be left to form itself, but must be practised diligently. Strong motivation is necessary, no half-hearted acquiescence in somebody else's injunction to get rid of the habit. We must adopt the counter-habit as ours, and work for a high standard of skill in it. For example, if we come to realize that we have a bad habit of grouchiness with our best friends, it is of little use merely to attempt to deaden this habit; we need to aim at being a positive addition to the company whenever we are present, and to practise the art of being good company, checking up our efforts to be sure we are hitting {329} the right vein, and persisting in our self-training till we become real artists. It takes some determination for a grouchy individual to make such a revolution in his conduct; his self-assertion resists violently, for the grouchiness is part and parcel of himself and he hates to be anything but himself. He must conceive a new and inspiring ideal of himself, and start climbing up the practice curve towards the new ideal.

EXERCISES

1. Outline the chapter.

2. Which of the acts performed in eating breakfast are instinctive, which are matters of habit, and which are partly the one and partly the other?

3. Compare your mental attitude in approaching an unfamiliar and a familiar task.

4. How does the performance of the expert in swimming or dancing, etc., differ from the performance of the beginner? Analyze out the points of superiority.

5. Show that the element of trial and error is present in (a) the child's learning to pronounce a word, and (b) learning "how to take" a person so as to get on well with him.

6. Why is it that our handwriting, though exercised so much, is apt to grow worse rather than better, while on the contrary our spelling is apt to improve?

7. How would you rate your efficiency in study? Is it near your physiological limit, on a plateau, or in a stage of rapid improvement?

8. A practice experiment. Take several pages of uniform printed matter, and mark it off into sections of 15 lines. Take your time for marking every word in one section that contains both e and r. The two letters need not be adjacent, but must both be present somewhere In the word. Having recorded your time for this first section, do the same thing with the next section, and so on for 12 sections. What were you able to observe, introspectively, of your method of work and changes with practice. From the objective observations, construct a practice curve.

9. Write brief explanations of the following terms:

practice
habit
higher unit
overlapping
plateau
physiological limit
insight
trial and error
negative adaptation
substitute stimulus
substitute response
conditioned reflex

REFERENCES

Thorndike's Animal Intelligence, Experimental Studies, 1911, reports his own pioneer work in this field. See also Chapter X in the same author's Educational Psychology, Briefer Course, 1914.

For other reviews of the work on animal learning, see Watson's Behavior, 1914, pp. 184-250; also Washburn's Animal Mind, 2nd edition, 1917, pp. 257-312.

For human learning and practice, see Thorndike's Educational Psychology, Briefer Course, 1914, Chapters XIV and XV; also Starch's Educational Psychology, 1919, Chapter XI.

For an experiment showing the acquisition of fears by a child, see Watson and Raynor, "Conditioned Emotional Reactions", in the Journal of Experimental Psychology, 1920, Vol. 3, pp. 1-14.

James's chapter on "Habit", in his Principles of Psychology, 1890, Vol. I, is a classic which every one should read.

CHAPTER XIV

MEMORY

HOW WE MEMORIZE AND REMEMBER, AND IN WHAT RESPECTS MEMORY CAN BE MANAGED AND IMPROVED

So much depends on a good memory in all walks of life, and especially in brain work of any sort, that perhaps it is no wonder that many students and business and professional men become worried about their memories and resort to "memory training courses" in the hope of improvement. The scientific approach to this very practical problem evidently lies through a careful study of the way in which memory works, and the general problem may be expressed in the question, how we learn and remember. This large problem breaks up, on analysis, into four subordinate questions: how we commit to memory, how we retain what has been committed to memory, how we get it back when we want it, and how we know that what we now get back is really what we formerly committed to memory. In the case of a person's name which we wish to remember, how do we "fix it in mind", how do we carry it around with us when we are not thinking of it, how do we call it up when needed, and what assures us that we have called up the right name? The four problems may be named those of

(1) Memorizing, or learning,
(2) Retention
(3) Recall
(4) Recognition

The Process of Memorizing

As memorizing is one sort of learning, what we have found in the preceding chapter regarding the learning process should throw light on our present problem. We found animals to learn by doing, and man by doing and also by observation or observation combined with doing. Observation is itself a form of doing, a mental reaction as distinguished from a purely passive or receptive state; so that learning is always active. Observation we found to be of great assistance, both by way of hastening the learning process, and by way of making what is learned more available for future use. Our previous studies of learning thus lead us to inquire whether committing to memory may not consist partly in rehearsing what we wish to learn, and partly in observing it. Learning by rote, or by merely repeating a performance over and over again, is, indeed, a fact; and observant study is also a fact.

Let us see how learning is actually done, as indicated by laboratory experiments. The psychologist experiments a great deal with the memorizing of nonsense material, because the process can be better observed here, from the beginning, than when sensible material is learned. Suppose a list of twenty one-place numbers is to be studied till it can be recited straight through. The learner may go at it simply by "doing", which means here by reading the list again and again, in the hope that it will finally stick. This pure rote learning will perhaps do the job, but it is slow and inefficient. Usually the learner goes to work in quite a different way. He observes various facts about the list. He notices what numbers occur at the beginning and end, and perhaps in other definite positions. He may group the digits into two-place or three-place numbers, and notice the characteristics of these. Any familiar combinations that {334} may occur, such as 1492, he is likely to spy and remember. Lacking these, he can at least find similar and contrasting number-groups.

For example, the list

5 7 4 0 6 2 7 3 5 1 4 0 9 2 8 6 3 8 0 1,

which at first sight seemed rather bare of anything characteristic, was analyzed in a way partly indicated by the commas and semicolons,

5, 74, 0; 62, 73; 5140; 9, 286; 380, 1,

and memorized easily. These observed facts transformed the list from a shapeless mass into something having definite characteristics, and the observed characteristics stuck in mind and held the rest together.

Lists of nonsense syllables, such as

wok pam zut bip seg ron taz vis lab mer koj yad

are apt to be learned largely by observation of similarities and contrasts, by reading meanings into the syllables, and by grouping into pairs and reading rhythmically. Grouping reduces the twelve syllables to six two-syllabled nonsense words, some of which may suggest meaningful words or at least have a swing that makes them easy to remember. Perhaps the first syllable of every pair is accented, and a pause introduced after each pair; such devices assist memorizing.

The rhythmical and other groups that are found or made by the learner in memorizing nonsense lists are, in effect, "higher units", and have much the same value as the higher units of telegraphy or typewriting. One who learns many lists in the course of a laboratory experiment develops a {335} regular system of grouping. First he reads the list through, in groups of two, three or four items, noticing each group as a whole; later, he notices the items in each group and how they are related to each other. He also notices the interrelations of different groups, and the position of each group in the total series. All this is quite different from a mere droning along through the items of the list; it is much more active, and much more observant.

Very interesting are the various ways in which the learner attacks a list of nonsense syllables, numbers, or disconnected words. He goes to work something like the cat trying to escape from a strange cage. He proceeds by a sort of trial and error observation; he keeps looking for something about the list that will help to fix it. He sees something that promises well for a moment, then gives it up because he sees something better. He notices positions, i.e., connects items with their position in the list. He finds syllables that stand out as peculiar in some way, being "odd", "fuzzy", smooth, agreeable, disagreeable, or resembling some word, abbreviation or nickname. He notes resemblances and contrasts between different syllables. He also finds groups that resemble each other, or that resemble words.

Besides what he actually finds in the list, he imports meanings, more or less far-fetched, into the list. He may make a rhythmical line of verse out of it; he may make a story out of it. In short, he both explores the list as it stands and manipulates it into some shape that promises to be rememberable.

His line of attack differs according to the particular test that is later to be made of his memory. Suppose he is shown a number of pictures, with the understanding that later those now shown are to be mixed with others, and that he must then pick out those now shown--then he simply examines each picture for something characteristic. But {336} suppose each picture is given a name, and he must later tell the name of each--then he seeks for something in the picture that can be made to suggest its name. Or suppose, once more, that the pictures are spread out before him in a row, and he is told that they will later be mixed and he be required to rearrange them in the same order in which they are now shown--then he seeks for relationships between the several pictures. His process of memorizing, always observant, exploratory and manipulatory, differs in detail according to the memory task that he expects later to perform.

For another example, suppose an experiment is conducted by the method of "paired associates". The subject is handed a list of pairs of words, such as

He must learn to respond with the second word of each pair when the first word of the pair is given. What he does, in learning this lesson, is to take each pair of words as a unit, and try to find something in the pair that shall make it a firm unit. It may be simply the peculiar sound or look of a pair that he notes, or it may be some connection {337} of meaning. Perhaps the pair suggests an image or a little story. After a few readings, he has the pairs so well in hand that he can score almost one hundred per cent., if tested immediately.

But now suppose the experimenter springs a surprise, by asking the subject, as far as possible, to recite the pairs in order, or to tell, after completing one pair, what was the first word of the next pair. The subject can do very little at this, and protests that the test is not fair, since he "paid no attention to the order of the pairs, but concentrated wholly on each pair separately". Had he expected to recite the whole list of pairs in order, he would have noticed the relationship of successive pairs, and perhaps woven them into a sort of continued story.

In memorizing connected passages of prose or poetry, the "facts observed" are the general sense and drift of the passage, the meanings of the parts and their places in the general scheme, the grammatical structure of the sentences and phrases, and the author's choice of particular words. Memorizing here is the same general sort of observant procedure as with nonsense material, greatly assisted by the familiar sequences of words and by the connected meaning of the passage, so that a connected passage can be learned in a fraction of the time needed to memorize an equally long list of unrelated words. No one in his senses would undertake to memorize an intelligible passage by the pure rote method, for this would be throwing away the best possible aid in memorizing; but you will find students who fail to take full advantage of the sense, because, reading along passively, they are not on the alert for general trends and outlines. For fixing in mind the sense of a passage, the essential thing is to see the sense. If the student gets the point with absolute clearness, he has pretty well committed it to memory.

Short-circuiting.

The peculiarities of words or syllables in a list or passage that is being memorized, the relationships observed among the parts, and the meanings suggested or imported into the material, though very useful in the early stages of memorizing, tend to drop out of mind as the material becomes familiar. A pair of syllables, "lub--mer", may have first been associated by turning them into "love mother", but later this meaning fades out, and the two syllables seem simply to belong together in their own right. A pair of words, like "seldom--harbor", that were first linked together by the intermediary thought of a boat that seldom came into the harbor, become directly bound together as mere words. A short-circuiting occurs, indirect attachments giving way to direct. Even the outline and general purpose of a connected passage may fade out of mind, when the passage becomes well learned, so that it may be almost impossible for a schoolboy, who has learned his little speech by heart, to deliver it with any consciousness of its real meaning. A familiar act flattens out and tends to become automatic and mechanical.

Economy in Memorizing

Memorizing is a form of mental work that is susceptible of management, and several principles of scientific management have been worked out that may greatly assist in the learning of a long and difficult lesson. The problem has been approached from the angle of economy or efficiency. Suppose a certain amount of time is allowed for the study of a lesson, how can this time be best utilized?

The first principle of economy has already been sufficiently emphasized: observant study, directed towards the finding of relationships and significant facts, is much more efficient than mere dull repetition.

The value of recitation in memorizing.

"Recitation" here means reciting to oneself. After the learner has read his lesson once or twice, he may, instead of continuing simply to read it, attempt to recite it, prompting himself without much delay when he is stuck, and verifying his recitation by reference to the paper. The question is whether this active reciting method of study is or is not economical of time in memorizing, and whether or not it fixes the lesson durably in memory. The matter has been thoroughly tested, and the answer is unequivocally in favor of recitation. The only outstanding question is as to how soon to start attempting to recite, and probably no single answer can be given to this question, so much depends on the kind of material studied, and on peculiarities of the individual learner. Where the sense rather than the exact wording of a lesson has to be learned, it is probably best to recite, in outline, after the first reading, and to utilize the next reading for filling in the outline.

The results of one series of experiments on this matter are summarized in the adjoining table.

Three facts stand out from the table: (1) Reading down the columns, we see that recitation was always an advantage. (2) The advantage was more marked in the test conducted four hours after study than in the test immediately following the study. To be sure, there is always a falling off from the immediate to the later test; there is bound to be some forgetting when the lesson has been studied for so short a time as here; but the forgetting proceeds more slowly after recitation than after all reading. Recitation fixes the matter more durably. (3) The advantage of recitation is less marked in the meaningful material than in case of nonsense syllables, though it is marked in both cases. The reason is that meaningful material can better be read observantly, time after time, than is possible with nonsense material. Continued reading of nonsense material degenerates into a mere droning, while in repeatedly reading meaningful material the learner who is keenly interested in mastering the passage is sure to keep his mind ahead of his eyes to some extent, so that his reading becomes half recitation, after all.

Whence comes the advantage of recitation? It has a twofold advantage: it is more stimulating, and it is more satisfying. When you know you are going to attempt recitation at once, you are stimulated to observe positions, peculiarities, relationships, and meanings, and thus your study {341} goes on at a higher level than when the test of your knowledge is still far away, with many readings still to come. You are also stimulated to manipulate the material, by way of grouping and rhythm.

On the side of satisfaction, recitation shows you what parts of the lesson you have mastered and gives you the glow of increasing success. It shows you exactly where you are failing and so stimulates to extra attention to those parts of the lesson. It taps the instincts of exploration, manipulation, and mastery much more effectively than continued re-reading of the same lesson can do. The latter becomes very uninteresting, monotonous and fatiguing.

Perhaps, after all, the greatest advantage of reciting is that it makes you do, in learning, the very act that you have later to perform in the test; for what you have finally to do is to recite the lesson without the book. When reading, you are doing something different; and if it were altogether different, it probably would not help you at all towards success in the test. But since intelligent reading consists partly in anticipating and outlining as you go, it is a sort of half recitation, it is halfway doing what you are trying to learn to do. Memorizing consists in performing an act, now, with assistance, that you later wish to perform without assistance; and recitation first stimulates you to fashion the act conformably to the object in view, and then exercises you in performing that act.

Spaced and unspaced repetition.

Another question on the economical management of memorizing: Is it better to keep steadily going through the lesson till you have it, or to go through it at intervals? If you were allowed a certain time, and no more, in which to prepare for examination on a certain memory lesson, how could the study time be best distributed? This question also has received a very definite answer.

Spaced repetitions are more effective than unspaced. In an experiment of Piéron, a practised subject went through a list of twenty numbers with an interval of only thirty seconds between readings, and needed eleven readings to master the list. But a similar list, with five-minute intervals, was mastered in six readings; and the number of readings went down to five with an interval of ten minutes, and remained the same for longer intervals up to two days. With this particular sort of lesson, then, ten minutes was a long enough interval, and two days not too long, to give the greatest economy of time spent in actual study.

In a somewhat different experiment in another laboratory, lists of nonsense syllables were studied either two, four, or eight times in immediate succession, and this was repeated each day till a total of twenty-four readings had been given to each list; then, one day after the last reading of each list, the subjects were tested as to their memory of it. The result appears in the adjoining table.

The widest distribution gave the best score. Undoubtedly, then, if you had to memorize a poem or speech, you would get better value for time spent if you read it once or twice at a time, with intervals of perhaps a day, than if you attempted to learn it at one continuous sitting. What exact spacing would give the very greatest economy would depend on the length and character of the lesson.

Spaced study also fixes the matter more durably. Every student knows that continuous "cramming" just before an {343} examination, while it may accomplish its immediate purpose, accomplishes little for permanent knowledge.

When we say that spaced repetitions give best results in memorizing, that does not mean that study generally should be in short periods with intervals of rest; it says nothing one way or the other on that question. The probability is, since most students take a certain time to get well "warmed up" to study, that fairly long periods of consecutive study would yield larger returns than the same amount of time divided into many short periods. What we have been saying here is simply that repetition of the same material fixes it better in memory, when an interval (not necessarily an empty interval) elapses between the repetitions.

Whole versus part learning.

In memorizing a long lesson, is it more economical to divide it into parts, and study each part by itself till mastered, or to keep the lesson entire and always go through the whole thing? Most of us would probably guess that study part by part would be better, but experimental results have usually been in favor of study of the whole.

If you had to memorize 240 lines of a poem, you would certainly be inclined to learn a part at a time; but notice the following experiment. A young man took two passages of this length, both from the same poem, and studied one by the whole method, the other by the part method, in sittings of about thirty-five minutes each day. His results appear in the table.

Here there was an economy of eighty-three minutes, or nearly twenty per cent., by using the whole method as against the part method. Similar experiments have regularly given the same general result.

However, the matter is not quite so simple, as, under certain conditions, the results tend the other way. Let us consider a very different type of learning test. A "pencil maze", consisting of passages or grooves to be traced out with a pencil, while the whole thing was concealed from the subject by a screen, was so arranged that it could be divided into four parts and each part learned separately. Four squads of learners were used. Squads A and B learned the maze as a whole, squads C and D part by part. Squads A and C learned by spaced trials, two trials per day. Squad B learned the whole thing at one sitting; while squad D, which came off best of all, learned one part a day for four days, and on the fifth day learned to put the parts together. The results appear in the adjoining table, which shows the average time required to master the maze by each of the four methods.

When the trials were spaced, the whole method was much the better; but when the trials were bunched, the part method was much the better; and, on the whole, the unspaced part learning was the best of all. Thus the result stands in apparent contradiction with two accepted laws: that of the advantage of spaced learning, and that of the advantage of whole learning.

This contradiction warns us not to accept the "laws" {345} too blindly, but rather to analyze out the factors of advantage in each method, and govern ourselves accordingly. Among the factors involved are the following four:

(1) The factor of interest, confidence and visible accomplishment--the emotional factor, we might call it. This is on the side of part learning, especially with beginners, who soon feel out of their depth when wading into a long lesson, and lose hope of ever learning it in this way. This factor is also largely on the side of unspaced as against spaced learning, when the part studied is of moderate length and when there are recitations to keep up the interest; for when the learner sees he is getting ahead, he would rather keep right on than wait for another day to finish. To have a task that you can hope to accomplish at once, and to attack it with the intention of mastering it at once, is very stimulating.

(2) The factor of recency, of "striking while the iron is hot". When an act has just been successfully performed it can easily be repeated, and when a fact has just been observed it can readily be put to use. This factor is clearly on the side of unspaced learning; and it is also on the side of part learning, since by the time you have gone through the whole long lesson and got back to where you are now, the recency value of what you have just now accomplished will have evaporated.

(3) The factor of meaning, outlining and broad relationships. This is on the side of whole learning, for it is when you are going through the whole that you catch its general drift, and see the connections of the several parts and their places in the whole. This factor is so important as to outweigh the preceding two in many cases, especially with experienced learners dealing with meaningful material. Even if you should prefer the part method, you would be wise to begin by a careful survey of the whole.

(4) The factor of permanency. This is something "physiological", and it is on the side of spaced learning. The muscles profit more by exercise with intervals of rest than by a large amount of continuous exercise, and no athlete would think for a moment of training for a contest of strength by "cramming" for it. Apparently the neurones obey the same law as the muscles, and for that reason spaced learning gives more durable results than unspaced.

Unintentional Learning

What we have been examining is intentional memorizing, with the "will to learn" strongly in the game. The assertion has sometimes been made that the will to learn is necessary if any learning is to be accomplished. We must look into this matter, for it has an important bearing on the whole question of the process of learning.

There is a famous incident that occurred in a Swiss psychological laboratory, when a foreign student was supposed to be memorizing a list of nonsense syllables. After the list had been passed before him many times without his giving the expected signal that he was ready to recite, the experimenter remarked that he seemed to be having trouble in memorizing the syllables. "Oh! I didn't understand that I was to learn them", he said, and it was found that, in fact, he had made almost no progress towards learning the list. He had been observing the separate syllables, with no effort to connect them into a series.

Another incident: subjects were put repeatedly through a "color naming test", which consisted of five colors repeated in irregular order, the object being to name the one hundred bits of color as rapidly as possible. After the subjects had been through this test over two hundred times, you would think they could recite it from memory; but not {347} at all! They had very little memory of the order of the bits of color. Their efforts had been wholly concentrated upon naming the bits as seen, and not in connecting them into a series that could be remembered.

The experiment described a few pages back on "paired associates" is another case in point. The subjects memorized the pairs, but made no effort to connect the pairs in order, and consequently were not able later to remember the order of the pairs.

Many somewhat similar experiments have been performed, with the object of measuring the reliability of the testimony of eye-witnesses; and it has been found that testimony is very unreliable except for facts that were specifically noted at the time. Enact a little scene before a class of students who do not suspect that their memory of the affair is later to be tested, and you will find that their memory for many facts that were before their eyes is hazy, absent, or positively false.

These facts all emphasize the importance of the will to learn. But let us consider another line of facts. An event occurs before our eyes, and we do notice certain facts about it, not with any intention of remembering them later, but simply because they arouse our interest; later, we recall such facts with great clearness and certainty. Or, we hear a tune time after time, and gradually come to be able to sing it ourselves, without ever having attempted to memorize it. Practically all that the child learns in the first few years of his life, he learns without any "will to learn".

What is the difference between the case where the will to learn is necessary, and the case where it is unnecessary? The difference is that in the one case we observe facts for the purpose of committing them to memory, and in the other case we observe the facts without any such intention. In both cases we remember what we have definitely observed, {348} and fail to remember what we have not observed. Sometimes, to be sure, it is not so much observation as doing that is operative. We may make a certain reaction with the object of learning it so as to make it later, or we may make the reaction for some other reason; but in either case we learn it.

What is essential, then, is not the will to learn, but the doing and observing. The will to learn is sometimes important, as a directive tendency, to steer doing and observing into channels relevant to the particular memory task that we need to perform. But committing to memory seems not to be any special form of activity; rather, it consists of reactions that also occur without any view to future remembering. Not only do we learn by doing and observing, but doing and observing are learning.

Retention

We come now to the second of our four main problems, and ask how we retain, or carry around inside of us, what we have learned. The answer is, not by any process or activity. Retention is a resting state, in which a learned reaction remains until the stimulus arrives that can arouse it again. We carry around with us, not the reaction, but the machinery for making the reaction.

Consider, for example, the retention of motor skill. A boy who has learned to turn a handspring does not have to keep doing it all the time in order to retain it. He may keep himself in better form by reviewing the performance occasionally, but he retains the skill even while eating and sleeping. The same can be said of the retention of the multiplication table, or of a poem, or of knowledge of any kind. The machinery that is retained consists very largely in brain connections. Connections formed in the process of {349} learning remain behind in a resting condition till again aroused to activity by some appropriate stimulus.

But the machinery developed in the process of learning is subject to the wasting effects of time. It is subject to the law of "atrophy through disuse". Just as a muscle, brought by exercise into the pink of condition, and then left long inactive, grows weak and small, so it is with the brain connections formed in learning. With prolongation of the condition of rest, the machinery is less and less able to function, till finally all retention of a once-learned reaction may be lost.

But is anything once learned ever completely forgotten and lost? Some say no, being strongly impressed by cases of recovery of memories that were thought to be altogether gone. Childhood experiences that were supposed to be completely forgotten, and that could not at first be recalled at all, have sometimes been recovered after a long and devious search. Sometimes a hypnotized person remembers facts that he could not get at in the waking state. Persons in a fever have been known to speak a language heard in childhood, but so long disused as to be completely inaccessible in the normal state. Such facts have been generalized into the extravagant statement that nothing once known is ever forgotten. For it is an extravagant statement. It would mean that all the lessons you had ever learned could still be recited, if only the right stimulus could be found to arouse them; it would mean that all the lectures you ever heard (and attended to) are still retained, that all the stories you ever read are still retained, that all the faces you ever noticed are still retained, that all the scenes and happenings that ever got your attention could still be revived if only the right means were taken to revive them. There is no evidence for any such extreme view.

The modern, scientific study of this matter began with {350} recognizing the fact that there are degrees of retention, ranging all the way from one hundred per cent, to zero, and with the invention of methods of measuring retention. Suppose you have memorized a list of twenty numbers some time ago, and kept a record of the time you then took to learn it; since when you have not thought of it again.