THE WILL AND VOLUNTARY ATTENTION.--In voluntary attention there is a conflict either between the will and interest or between the will and the mental inertia or laziness, which has to be overcome before we can think with any degree of concentration. Interest says, "Follow this line, which is easy and attractive, or which requires but little effort--follow the line of least resistance." Will says, "Quit that line of dalliance and ease, and take this harder way which I direct--cease the line of least resistance and take the one of greatest resistance."
When day dreams and "castles in Spain" attempt to lure you from your lessons, refuse to follow; shut out these vagabond thoughts and stick to your task. When intellectual inertia deadens your thought and clogs your mental stream, throw it off and court forceful effort. If wrong or impure thoughts seek entrance to your mind, close and lock your mental doors to them. If thoughts of desire try to drive out thoughts of duty, be heroic and insist that thoughts of duty shall have right of way. In short, see that _you_ are the master of your thinking, and do not let it always be directed without your consent by influences outside of yourself.
It is just at this point that the strong will wins victory and the weak will breaks down. Between the ability to control one"s thoughts and the inability to control them lies all the difference between right actions and wrong actions; between withstanding temptation and yielding to it; between an inefficient purposeless life and a life of purpose and endeavor; between success and failure. For we act in accordance with those things which our thought rests upon. Suppose two lines of thought represented by _A_ and _B_, respectively, lie before you; that _A_ leads to a course of action difficult or unpleasant, but necessary to success or duty, and that _B_ leads to a course of action easy or pleasant, but fatal to success or duty. Which course will you follow--the rugged path of duty or the easier one of pleasure? The answer depends almost wholly, if not entirely, on your power of attention. If your will is strong enough to pull your thoughts away from the fatal but attractive _B_ and hold them resolutely on the less attractive _A_, then _A_ will dictate your course of action, and you will respond to the call for endeavor, self-denial, and duty; but if your thoughts break away from the domination of your will and allow the beckoning of your interests alone, then _B_ will dictate your course of action, and you will follow the leading of ease and pleasure. _For our actions are finally and irrevocably dictated by the things we think about._
NOT REALLY DIFFERENT KINDS OF ATTENTION.--It is not to be understood, however, from what has been said, that there are _really_ different kinds of attention. All attention denotes an active or dynamic phase of consciousness. The difference is rather _in the way we secure attention_; whether it is demanded by sudden stimulus, coaxed from us by interesting objects of thought without effort on our part, or compelled by force of will to desert the more interesting and take the direction which we dictate.
6. IMPROVING THE POWER OF ATTENTION
While attention is no doubt partly a natural gift, yet there is probably no power of the mind more susceptible to training than is attention. And with attention, as with every other power of body and mind, the secret of its development lies in its use. Stated briefly, the only way to train attention is by attending. No amount of theorizing or resolving can take the place of practice in the actual process of attending.
MAKING DIFFERENT KINDS OF ATTENTION REeNFORCE EACH OTHER.--A very close relationship and interdependence exists between nonvoluntary and voluntary attention. It would be impossible to hold our attention by sheer force of will on objects which were forever devoid of interest; likewise the blind following of our interests and desires would finally lead to shipwreck in all our lives. Each kind of attention must support and reenforce the other. The lessons, the sermons, the lectures, and the books in which we are most interested, and hence to which we attend nonvoluntarily and with the least effort and fatigue, are the ones out of which, other things being equal, we get the most and remember the best and longest. On the other hand, there are sometimes lessons and lectures and books, and many things besides, which are not intensely interesting, but which should be attended to nevertheless. It is at this point that the will must step in and take command. If it has not the strength to do this, it is in so far a weak will, and steps should be taken to develop it. We are to "_keep the faculty of effort alive in us by a little gratuitous exercise every day_." We are to be systematically heroic in the little points of everyday life and experience. We are not to shrink from tasks because they are difficult or unpleasant. Then, when the test comes, we shall not find ourselves unnerved and untrained, but shall be able to stand in the evil day.
THE HABIT OF ATTENTION.--Finally, one of the chief things in training the attention is _to form the habit of attending_. This habit is to be formed only by _attending_ whenever and wherever the proper thing to do is to attend, whether "in work, in play, in making fishing flies, in preparing for an examination, in courting a sweetheart, in reading a book." The lesson, or the sermon, or the lecture, may not be very interesting; but if they are to be attended to at all, our rule should be to attend to them completely and absolutely. Not by fits and starts, now drifting away and now jerking ourselves back, but _all the time_.
And, furthermore, the one who will deliberately do this will often find the dull and uninteresting task become more interesting; but if it never becomes interesting, he is at least forming a habit which will be invaluable to him through life. On the other hand, the one who fails to attend except when his interest is captured, who never exerts effort to compel attention, is forming a habit which will be the bane of his thinking until his stream of thought shall end.
7. PROBLEMS IN OBSERVATION AND INTROSPECTION
1. Which fatigues you more, to give attention of the nonvoluntary type, or the voluntary? Which can you maintain longer? Which is the more pleasant and agreeable to give? Under which can you accomplish more?
What bearing have these facts on teaching?
2. Try to follow for one or two minutes the "wave" in your consciousness, and then describe the course taken by your attention.
3. Have you observed one cla.s.s alert in attention, and another lifeless and inattentive? Can you explain the causes lying back of this difference? Estimate the relative amount of work accomplished under the two conditions.
4. What distractions have you observed in the schoolroom tending to break up attention?
5. Have you seen pupils inattentive from lack of (1) change, (2) pure air, (3) enthusiasm on the part of the teacher, (4) fatigue, (5) ill health?
6. Have you noticed a difference in the _habit_ of attention in different pupils? Have you noticed the same thing for whole schools or rooms?
7. Do you know of children too much given to daydreaming? Are you?
8. Have you seen a teacher rap the desk for attention? What type of attention was secured? Does it pay?
9. Have you observed any instance in which pupils" lack of attention should be blamed on the teacher? If so, what was the fault? The remedy?
10. Visit a school room or a recitation, and then write an account of the types and degrees of attention you observed. Try to explain the factors responsible for any failures in attention, and also those responsible for the good attention shown.
CHAPTER III
THE BRAIN AND NERVOUS SYSTEM
A fine brain, or a good mind. These terms are often used interchangeably, as if they stood for the same thing. Yet the brain is material substance--so many cells and fibers, a pulpy protoplasmic ma.s.s weighing some three pounds and shut away from the outside world in a casket of bone. The mind is a spiritual thing--the sum of the processes by which we think and feel and will, mastering our world and accomplishing our destiny.
1. THE RELATIONS OF MIND AND BRAIN
INTERACTION OF MIND AND BRAIN.--How, then, come these two widely different facts, mind and brain, to be so related in our speech? Why are the terms so commonly interchanged?--It is because mind and brain are so vitally related in their processes and so inseparably connected in their work. No movement of our thought, no bit of sensation, no memory, no feeling, no act of decision but is accompanied by its own particular activity in the cells of the brain. It is this that the psychologist has in mind when he says, _no psychosis without its corresponding neurosis_.
So far as our present existence is concerned, then, no mind ever works except through some brain, and a brain without a mind becomes but a ma.s.s of dead matter, so much clay. Mind and brain are perfectly adapted to each other. Nor is this mere accident. For through the ages of man"s past history each has grown up and developed into its present state of efficiency by working in conjunction with the other. Each has helped form the other and determine its qualities. Not only is this true for the race in its evolution, but for every individual as he pa.s.ses from infancy to maturity.
THE BRAIN AS THE MIND"S MACHINE.--In the first chapter we saw that the brain does not create the mind, but that the mind works through the brain. No one can believe that the brain secretes mind as the liver secretes bile, or that it grinds it out as a mill does flour. Indeed, just what their exact relation is has not yet been settled. Yet it is easy to see that if the mind must use the brain as a machine and work through it, then the mind must be subject to the limitations of its machine, or, in other words, the mind cannot be better than the brain through which it operates. A brain and nervous system that are poorly developed or insufficiently nourished mean low grade of efficiency in our mental processes, just as a poorly constructed or wrongly adjusted motor means loss of power in applying the electric current to its work.
We will, then, look upon the mind and the brain as counterparts of each other, each performing activities which correspond to activities in the other, both inextricably bound together at least so far as this life is concerned, and each getting its significance by its union with the other. This view will lend interest to a brief study of the brain and nervous system.
2. THE MIND"S DEPENDENCE ON THE EXTERNAL WORLD
But can we first see how in a general way the brain and nervous system are primarily related to our thinking? Let us go back to the beginning and consider the babe when it first opens its eyes on the scenes of its new existence. What is in its mind? What does it think about? Nothing.
Imagine, if you can, a person born blind and deaf, and without the sense of touch, taste, or smell. Let such a person live on for a year, for five years, for a lifetime. What would he know? What ray of intelligence would enter his mind? What would he think about? All would be dark to his eyes, all silent to his ears, all tasteless to his mouth, all odorless to his nostrils, all touchless to his skin. His mind would be a blank. He would have no mind. He could not get started to think. He could not get started to act. He would belong to a lower scale of life than the tiny animal that floats with the waves and the tide in the ocean without power to direct its own course. He would be but an inert ma.s.s of flesh without sense or intelligence.
THE MIND AT BIRTH.--Yet this is the condition of the babe at birth. It is born practically blind and deaf, without definite sense of taste or smell. Born without anything to think about, and no way to get anything to think about until the senses wake up and furnish some material from the outside world. Born with all the mechanism of muscle and nerve ready to perform the countless complex movements of arms and legs and body which characterize every child, he could not successfully start these activities without a message from the senses to set them going. At birth the child probably has only the senses of contact and temperature present with any degree of clearness; taste soon follows; vision of an imperfect sort in a few days; hearing about the same time, and smell a little later. The senses are waking up and beginning their acquaintance with the outside world.
[Ill.u.s.tration: FIG. 5.--A NEURONE FROM A HUMAN SPINAL CORD. The central portion represents the cell body. N, the nucleus; P, a pigmented or colored spot; D, a dendrite, or relatively short fiber,--which branches freely; A, an axon or long fiber, which branches but little.]
THE WORK OF THE SENSES.--And what a problem the senses have to solve! On the one hand the great universe of sights and sounds, of tastes and smells, of contacts and temperatures, and whatever else may belong to the material world in which we live; and on the other hand the little shapeless ma.s.s of gray and white pulpy matter called the brain, incapable of sustaining its own shape, shut away in the darkness of a bony case with no possibility of contact with the outside world, and possessing no means of communicating with it except through the senses.
And yet this universe of external things must be brought into communication with the seemingly insignificant but really wonderful brain, else the mind could never be. Here we discover, then, the two great factors which first require our study if we would understand the growth of the mind--_the material world without, and the brain within_.
For it is the action and interaction of these which lie at the bottom of the mind"s development. Let us first look a little more closely at the brain and the accompanying nervous system.
3. STRUCTURAL ELEMENTS OF THE NERVOUS SYSTEM
It will help in understanding both the structure and the working of the nervous system to keep in mind that it contains _but one fundamental unit of structure_. This is the neurone. Just as the house is built up by adding brick upon brick, so brain, cord, nerves and organs of sense are formed by the union of numberless neurones.
[Ill.u.s.tration: FIG. 6.--Neurones in different stages of development, from _a_ to _e_. In _a_, the elementary cell body alone is present; in _c_, a dendrite is shown projecting upward and an axon downward.--After DONALDSON.]
THE NEURONE.--What, then, is a neurone? What is its structure, its function, how does it act? A neurone is _a protoplasmic cell, with its outgrowing fibers_. The cell part of the neurone is of a variety of shapes, triangular, pyramidal, cylindrical, and irregular. The cells vary in size from 1/250 to 1/3500 of an inch in diameter. In general the function of the cell is thought to be to generate the nervous energy responsible for our consciousness--sensation, memory, reasoning, feeling and all the rest, and for our movements. The cell also provides for the nutrition of the fibers.
[Ill.u.s.tration: FIG. 7.--Longitudinal (a) and Transverse (b) section of nerve fiber. The heavy border represents the medullary, or enveloping sheath, which becomes thicker in the larger fibers.--After DONALDSON.]
NEURONE FIBERS.--The neurone fibers are of two kinds, _dendrites_ and _axons_. The dendrites are comparatively large in diameter, branch freely, like the branches of a tree, and extend but a relatively short distance from the parent cell. Axons are slender, and branch but little, and then approximately at right angles. They reach a much greater distance from the cell body than the dendrites. Neurones vary greatly in length. Some of those found in the spinal cord and brain are not more than 1/12 of an inch long, while others which reach from the extremities to the cord, measure several feet. Both dendrites and axons are of diameter so small as to be invisible except under the microscope.
NEUROGLIA.--Out of this simple structural element, the neurone, the entire nervous system is built. True, the neurones are held in place, and perhaps insulated, by a kind of soft cement called _neuroglia_. But this seems to possess no strictly nervous function. The number of the microscopic neurones required to make up the ma.s.s of the brain, cord and peripheral nervous system is far beyond our mental grasp. It is computed that the brain and cord contain some 3,000 millions of them.
COMPLEXITY OF THE BRAIN.--Something of the complexity of the brain structure can best be understood by an ill.u.s.tration. Professor Stratton estimates that if we were to make a model of the human brain, using for the neurone fibers wires so small as to be barely visible to the eye, in order to find room for all the wires the model would need to be the size of a city block on the base and correspondingly high. Imagine a telephone system of this complexity operating from one switch-board!
"GRAY" AND "WHITE" MATTER.--The "gray matter" of the brain and cord is made up of nerve cells and their dendrites, and the terminations of axons, which enter from the adjoining white matter. A part of the ma.s.s of gray matter also consists of the neuroglia which surrounds the nerve cells and fibers, and a network of blood vessels. The "white matter" of the central system consists chiefly of axons with their enveloping or medullary, sheath and neuroglia. The white matter contains no nerve cells or dendrites. The difference in color of the gray and the white matter is caused chiefly by the fact that in the gray ma.s.ses the medullary sheath, which is white, is lacking, thus revealing the ashen gray of the nerve threads. In the white ma.s.ses the medullary sheath is present.
4. GROSS STRUCTURE OF THE NERVOUS SYSTEM
DIVISIONS OF THE NERVOUS SYSTEM.--The nervous system may be considered in two divisions: (1) The _central_ system, which consists of the brain and spinal cord, and (2) the _peripheral_ system, which comprises the sensory and motor neurones connecting the periphery and the internal organs with the central system and the specialized end-organs of the senses. The _sympathetic_ system, which is found as a double chain of nerve connections joining the roots of sensory and motor nerves just outside the spinal column, does not seem to be directly related to consciousness and so will not be discussed here. A brief description of the nervous system will help us better to understand how its parts all work together in so wonderful a way to accomplish their great result.