XIII
THE STREAM OF THOUGHT

In speaking of our inner life we employ language that abounds in metaphors drawn from the external world. Some are faded metaphors; others are still fresh and new enough to suggest what was in the minds of those first using them. Many of these metaphorical expressions draw attention to one side or phase of the truth. If pressed with the design of making them embody the whole truth, they become untruths.

One fact of our waking consciousness is that thought goes on without stopping so long as we remain awake. Indeed, some philosophers have drawn the inference that the soul always thinks, that during the hours of deep sleep the brain-centres may be at rest, but that thought nevertheless flows on in the unconscious depths of our being. Locke combats this idea at length and with more than usual warmth. During sleep on a railway train we sometimes seem to be awake, the ends of our conscious thinking apparently fitting into each other without gaps; and yet the calling out of the stations convinces us that we must have been wrapped in unconscious slumber when we passed certain stations without noticing that the train stopped and the stations were announced. On the other hand, it is the experience of earnest students that the striking of a clock may escape notice because the mind has been deeply absorbed in a difficult problem.

The question need not concern us beyond the fact that the thinking of our most wakeful moments perpetually plays into our subconscious life. In order that the flow of thought welling up from the deepest depths of the soul may be clear, copious, and full, it is the duty of the teacher to keep himself and his pupils wide awake during the hours of study and recitation. He should not worry them by excessive tasks or unreasonable examinations so that the hours of sleep are disturbed by dreams, followed during the day by weariness and fatigue. The folly of burning the midnight oil and of spending too many hours each day in mental toil is fraught with evil consequences in the domain of thought. In the main Harbaugh was right when he undertook to change Franklin’s maxim about early rising into the following form: “Go to bed early, and get up late; but then keep awake all day.”

So far as we are aware, thought is going forward continuously while we are awake. This phase of consciousness has been likened to a stream, and has given rise to the expression, The stream of thought. The metaphor can be pressed very far without conveying untruths. A stream does not always flow with the same velocity. It is at times deep, at other times shallow, now moving forward like a swollen torrent, now flowing placidly with scarcely a wave or a ripple perceptible on its surface. Here its smooth course is disturbed by wind and storm and rain; there its even flow is influenced by rocks and irregularities in the bed of the stream. Again and again its current is modified by affluents which empty their waters into the main stream, perhaps changing the appearance from clear to cloudy or muddy, or, it may be, exerting the opposite effect. To all these peculiarities in the flow of the stream there are likenesses in the stream of thought. At times it is deep and at other times shallow, now violent and disturbed, now calm and placid, sometimes clear to the bottom, sometimes cloudy, yea, muddy, always modified more or less by influences from without, which are taken up into the main current of thought and alter the stream like the tributaries of a great river.

On reaching the level country a river may spread out into a lake, resulting in a clearing up of the water and resembling the periods of calm meditation during which the soul clarifies its thinking. The lifelike behavior of rivers and the carving of land forms from their youth through maturity to old age have furnished many a figure of speech for our poetic literature. The change from the active upper waters to the sedate lower current may typify the change in the stream of thought as we pass from youth to age. While the volume of the stream is small and the channel lacks depth, it is easy to change the direction of the current, as sometimes happens when a straight channel is dug to take the place of its windings. In early life the stream of thought is apt to wander in meandering courses; the teacher may very frequently find it necessary to keep the mind from wandering, to direct the stream of thought towards the destined goal, and to make it groove for itself channels in harmony with logical habits. In teaching pupils to think it is quite as essential to give direction to thought as it is to furnish either thought-stimulus or thought-material. In one respect the metaphor, stream of thought, fails utterly to express the truth. The constituents of thought are not related to each other like the molecules of a liquid which move freely among themselves. Thoughts have a connection with those that precede and those that follow. An inner nexus binds the successive portions of a demonstration. Hence other figures of speech have been employed to denote the connection between the successive elements of a logical proof, such as the train of thought, the line of argument, the chain of reasoning.

It will be readily admitted that often our thinking is so loose and disjointed that its component parts resemble the liquid more than the chain, whereas our best thinking—namely, that which leads to a goal in the shape of a trustworthy conclusion—resembles a train of cars in which motive power is derived not from steam, but from a conscious expenditure of will-power. The teacher may perform the triple function of fireman, engineer, and switch-tender, supplying the fuel for the process, regulating the speed, and directing it along the lines of track which lead to the desired goal. It is as natural for a pupil to think as it is for a stream to flow towards the ocean. The stream may run shallow if no supply of water is received from the outside. It is the mission of the teacher to keep up the supply, to remove as far as possible the obstructions which are likely to throw the current of thought into unexpected channels. It is a peculiarity of this current of thinking that it is cognitive, or possesses the function of knowing. Human thought resembles the stream in seemingly taking up and carrying what was not a part of itself. Just as the stream of water carries minerals in solution as well as silt, sand, pebbles, and even heavier objects, so the stream of thought appears to lay hold of objects and to carry them as part of itself. Here, however, the strings of the analogy break. The stream of thought is in the mind; the objects with which it deals are outside of the mind. Mental pictures of these objects float in the stream of thought as objects on the bank of a river are mirrored in its waters; yet the parallel is not complete, because the mind may turn the eye upon itself and make what is thus seen the object of thought. This turning upon itself may be likened to eddies in the stream. But even when the mind thus turns back upon itself and views its own states and activities, these are regarded as objective, as related to the thinking process very much like the objects of knowledge in the external world.

Another important phase of thinking finds no likeness in any of the figures of speech above referred to. The mind meets certain objects of thought on which it seems to tarry or fasten itself. This has led some writers to deny that the stream of thought is a continuous current. This view causes undue stress to be laid upon the material of thought, and leads the teacher to undervalue his function as directing guide in teaching pupils to think. Even Professor Bain claims that,—

“The stream of thought is not a continuous current, but a series of distinct ideas, more or less rapid in their succession, the rapidity being measurable by the number that pass through the mind in a given time. Mental excitement is constantly judged of by this test; and if we choose to count and time the thoughts as they succeed one another, we could give so much more precision to the estimate.”[32]

These transitions should not be confounded with the relations between objects of thought or between objects in the external world. The relations may be part of the thought of that which is perceived or known, or they may be made distinct ideas or thoughts. The important phase under consideration is the passage of the mind from one idea or thought to another. Such transitions are quite as important and quite as much a part of the current of thought as the premises and conclusions on which the mind seems to rest. These two phases of the thought-process may be likened to the perching and the flight of a bird. This figure of speech is used by Professor James, among whose services to the profession of teaching it is not the least that he has called attention to the importance of these transitions in the stream of consciousness. His account is so lucid and satisfactory that one cannot forbear to quote his words at some length. Referring to the stream of thought, he says,—

“Like a bird’s life, it seems to be made up of an alternation of flights and perchings. The rhythm of language expresses this, where every thought is expressed in a sentence and every sentence closed by a period. The resting-places are usually occupied by sensorial imaginations of some sort, whose peculiarity is that they can be held before the mind for an indefinite time and contemplated without changing; the places of flight are filled with thoughts of relations, static or dynamic, that for the most part obtain between the matters contemplated in the periods of comparative rest. Let us call the halting-places the ‘substantive’ parts and the places of flight the ‘transitive’ parts of the stream of thought. It then appears that the main need of our thinking is at all times the attainment of some other substantive part than the one from which we have just been dislodged. And we may say that the main use of the transitive parts is to lead us from one substantive conclusion to another. Now it is very difficult, introspectively, to see the transitive parts for what they really are. If they are but flights to a conclusion, stopping them to look at them before a conclusion is reached is really annihilating them. Whilst if we wait until the conclusion be reached, it so exceeds them in vigor and stability that it quite eclipses and swallows them up in its glare. Let any one try to cut a thought in the middle and get a look at its section, and he will see how difficult the introspective observation of the transitive tract is. The rush of the thought is so headlong that it almost always brings us up at the conclusion before we can arrest it. Or if our purpose is nimble enough and we do arrest it, it ceases forthwith to be itself. As a snow-flake crystal caught in the warm hand is no longer a crystal, but a drop, so, instead of catching the feeling of relation moving to its term, we find we have caught some substantive thing, usually the last word we were pronouncing, statistically taken, and with its function, tendency, and particular meaning in the sentence quite evaporated. The attempt at introspective analysis in these cases is, in fact, like seizing a spinning top to catch its motion, or trying to turn up the gas quickly enough to see the darkness. And the challenge to produce these psychoses, which is sure to be thrown by doubting psychologists at any one who contends for their existence, is as unfair as Zeno’s treatment of the advocates of motion, when, asking them to point out in what place an arrow is when it moves, he argues the falsity of their thesis from their inability to make to so preposterous a question an immediate reply.”[33]

The science of logic deals almost altogether with the halting-places, with the substantive parts, with the ideas, notions, concepts that are to be compared, and with the resulting judgments, inferences, and conclusions. Whether the teacher has studied the science of logic or not, it is to these he devotes his chief attention; they can be analyzed, defined, and clearly fixed as thought-products or knowledge. Defects in the thinking-process are apt to show themselves here; at least, they furnish tangible data for criticism, corrections, and reviews. These thought-products on which the mind loves to linger are denoted by nouns, verbs, adjectives, and adverbs,—the parts of speech which constitute the bulk of the vocabulary of every language. The movements of the mind from one object of thought to another are indicated by conjunctions and other connectives. Thinkers are often known by their favorite connective words and phrases. Pupils catch these from the phraseology of their teachers, or pick them up unconsciously from the books they read. Some languages are richer in such connective words and phrases than others; the mind carries away some influence in the way of making these transitions in thought from every language which it studies; its thinking is moulded by the language which it masters. Logic has very little to say about these transitions for which one language sometimes supplies words and expressions altogether wanting in another. Frequently we grow conscious of them through the feeling of a gap to be filled, or of a chasm to be leaped over, or of an obstacle to be cleared away, or of something that obstructs our thinking and hinders it from reaching the goal. Here again one cannot refrain from quoting Professor James, although his words do not indicate that he fully realizes the value for elementary instruction of what he has written. Here are his words:

“The truth is that large tracts of human speech are nothing but signs of direction in thought, of which direction we, nevertheless, have an acutely discriminative sense, though no definite sensorial image plays any part in it whatsoever. Sensorial images are stable psychic facts; we can hold them still, and look at them as long as we like. These bare images of logical movements, on the contrary, are psychic transitions, always on the wing, so to speak, and not to be glimpsed except in flight. Their function is to lead from one set of images to another. As they pass, we feel both the waxing and the waning images in a way quite different from the way of their full presence. If we try to hold fast the feeling of direction, the full presence comes, and the feeling of direction is lost. The blank verbal scheme of logical movement gives us the fleeting sense of the movement as we read it, quite as well as does a rational sentence awakening definite imaginations by its words.”[34]

Right here the teacher who is an artist finds the opportunity for the display of his highest skill. It is his privilege to direct the flights and the perchings of the youthful mind. He can shape the thoughts and their sequence. He can cause the intellect to move from the reason to its consequence, or in the reverse direction if that be more natural or more appropriate. He can guide the thought from cause to effect, from the whole to the parts, from the general to the particular, from the end to the means, from the design to its execution; or a movement the other way is possible in each of these categories. While thus choosing the direction which thought shall take, he can select the objects upon which it shall tarry. This directing influence he will often exert when he is not aware of it. His own habits of mind will be reflected in the mental life of his pupils. There was profound philosophy in the reply of a gifted author who, when asked by his daughter what she should study, said, “I am more concerned about the teachers under whom you study than about the branches of study which you may select.” Habits of thought depend far more upon the teacher than upon the text-book, upon the quality of the instruction than upon its general content. There is, of course, a difference in the culture value of different branches of study; but a study as valuable as geometry may be pursued in a loose way, whilst branches of much inferior value for developing power to think may be taught and studied by the methods of rigid and exact thought.

In shaping the activity of thought, the artist-teacher makes the mind tarry long enough for clear apprehension, sometimes for thorough comprehension, upon the ideas, judgments, and conclusions which are the framework of a system of thought, but he does not neglect the transitions from one to the other, as if these were of little account or necessarily took care of themselves. The transitions in thought are aided by set phrases and forms of solution. As soon as these are mastered, there develops the tendency to think them as algebraic symbols, which do substitute duty in the absence of that for which they stand. For fear of this, the teacher sometimes fails to drill on them long enough to fix them in the mind,—certainly a radical mistake. Drill is a condition of the highest discipline in the school as well as in the army. The drill-master seeks to habituate the soldier to the word of command, so that he will obey in the face of danger without thinking of the consequences. The drill-master at school seeks to make it second nature for a pupil to go through the logical motions, but not without conscious thought of the process or the consequences. Whenever the learner uses forms of parsing, analysis, or solution, his mind should go through the movements of thought expressed by the language. Ask any ordinary class to give you a noun of the first person; they are almost sure to give you either a noun of the third person or a pronoun of the first person. Dictate a sentence with a noun in the first person, and ask the pupils to parse it in the customary way; in nearly all cases they will parse it as a noun of the third person. Ask them to tell why a personal pronoun is so called; frequently they say because it indicates a person,—a statement quite applicable to other kinds of pronouns. If the logical or customary forms of speech are employed, the stream of thought moves on, the mind often failing to perceive the new truth, or error, or nonsense inherent in the language employed. School-boys have tricks of their own which turn upon this peculiarity in the movement of thought. “Who killed Cain?” is suddenly asked. “Abel,” is the reply generally elicited by the question. Should you say, Nine times seven is or are forty-two? The boy who decides in favor of is or are gets a shock of surprise on being told that the product of nine times seven is not forty-two.

One day a teacher was lecturing upon education in the dark ages. To show how the energies of the common people were exhausted in the struggle for existence, the resolution of a synod in the south of France was cited. The resolution enjoined upon the bishops the duty of seeing to it that during a period of scarcity of food the peasants were at least provided with bread made of acorns. A few minutes later a reference was made to the autobiography of Thomas Platter, in which certain things are described as happening about the time of the Diet of Worms. On being asked in what period of history that was, a pupil promptly replied, “When the common people were fed on worms.”

Very much of the sermonizing of our day gives rise to the same kind of thinking. The mind is borne along by the customary flow of words. The phrases used have an orthodox sound; perhaps they are biblical in the sense that they occur in the Bible. It is impossible to tell whether any clear idea or real religious experience is suggested to the hearer’s mind by the words used. The ideas excited in the hearer should be those for which the words stand in the mind of the speaker. If the ideas of the speaker are not clear, how can his words suggest anything definite to the audience? Huxley relates an amusing story of an after-dinner orator who was endowed with a voice of rare flexibility and power, and with a fine flow of words, and who was called upon to speak without much preparation. The applause was terrific. When Huxley asked a neighbor who was especially enthusiastic what the orator had said, the latter could not tell. Nothing was lacking in the post-prandial speech save sense and occasionally grammar.[35]

The fuller consideration of the stream of thought in listening and lecturing, in reading, speaking, and composing, is deserving of separate chapters. The mental attitude in listening resembles that in getting thought from the printed page. Silent reading is for the reader’s own benefit; it comprises by far the larger proportion of our reading. In oral reading, the stream of thought is somewhat different, the aim being similar to that of public speaking,—namely, to suggest or convey to the hearer thoughts from some other mind. In the act of composing, the aim is to evolve thought from the mind’s own resources and activities. The thought process is very much the same, no matter whether we dictate to a stenographer, or speak to an audience, or use the pen in giving to it form and abiding shape. It will be most convenient to treat together the stream of thought in listening and in silent reading, and to reserve for separate consideration the activity of the mind in writing, speaking, and oral reading.