of the stormy sea represent the essentially dynamic property of attention. Attention, like all work, is movement. At every instant we have to pass onwards, and we halt only as long as there is something for us to do.*

30.-NARROWING THE NORMAL FIELD OF ATTENTION.

Let us begin with an illustration. It is some time since I visited a certain friend. As I enter a street near that friend's house, I see his terrier who used to accompany me on my rambles. I shout across the road "Cæsar." The dog instantly turns. His head and neck, his limbs, his tail, his whole body, in short, appear rigid and motionless. His eyes are vacant. His breathing, I suspect, has almost ceased. After a few moments the eyes suddenly brighten, the body becomes a volume of living springs, and the dog bounds over to me. I am recognised by him. My voice apparently has struck some familiar chord, for else he would have taken no notice of my call. His whole being, we may say, has been sucked into the whirlpool of a known voice. The available attention, under these exceptional circumstances, was centred on one detail. From his stiffness and his blank gaze, it was clear that all central activity, except that of deciphering my personality, was absent. His eyes, his ears, his nostrils, his imagination, struck work. Energy was sorely needed in one direction, and was, therefore, withdrawn from other directions.

In this instance the field of immediately traceable activity was reduced almost to zero. There was not merely an exchange of one field for another; but the second field had almost no dimensions. The attention machinery, which would normally produce a certain quantity of immediately traceable detail, was working subterraneously. We meet here with purposive vacancy. Compared with ordinary thought, we miss subject, points of subject and sense elements. Otherwise there are but confused feelings to make up for the extraordinary shrinkage of the view; perhaps even these are absent. It is a narrowing of the traceable field of attention with a corresponding reduction of traceable activity. [Examine such cases carefully.]

Such shrinkage is produced on various occasions, notably: (1) when we are trying hard to re-collect something; (2) when we put a difficult question to ourselves and insist on obtaining an answer; (3) when we attempt to grasp an intricate problem, as in the case of understanding what we read; (4) when we wish to think of a subject under unfavourable circumstances as in ignoring a conversation going on around us; (5) when we slip into bed, close our eyes, and make ready for sleep; (6) when we are subjected to long-continued and monotonous stimulation, as when the hypnotic state is induced; and, lastly, (7) when we are on the qui vive as regards some

As to certain minute oscillations of the attention, as when listening to a just perceptible sound, see especially Münsterberg, Schwankungen der Aufmerksamkeit, Beiträge, 1889, Heft 2; also Hylan, Fluctuations of the Attention, 1896 and 1898; Urbantschitsch, Pflüger's Archiv, 1881 and 1882, and Centralblatt f. d. Med. Wissenschaft, 1875; Cook, Fluctuation of the Attention to Musical Tones, 1899; and, in Wundt's Phil Studien, Lange (1887), Eckener and Pace (1892), Marbe and Lehmann (1893).

matter, as in endeavouring to hear whether a nightingale is singing in the distance. [Test the whole list and add to it.] In all these instances our neural system is like a stretched elastic band which has a strong tendency to return to its normal condition. If we persist in such an attitude for long, we invite headache and dizziness. Usually, therefore, our attempts are consecutive; but even then frequent trials, at short intervals, to narrow the field of attention defeat themselves.

31.-EXPANDing the NorMAL FIELD OF ATTENTION.

The normal field of attention may be narrowed. May it also be expanded? That does not appear possible. [Challenge this statement.] Suppose that we desire to observe all that is passing around us. We act accordingly, and we soon learn that no appreciable growth of the field of attention has taken place. What happens is that we quickly fly from detail to detail, the peculiar excitement favouring retention of what is observed. It may be, however, that excitement induces a more than usually voluminous and rapid flow of thought.

32. BRAIN AND MIND.

Assuming that the brain resembles the other portions of the human organism, then what we have stated in the four preceding sections is in accordance with what we should expect. Take for an illustration the arm. The same human being, at his stage of development, puts forth about the same exertion. Strenuous and monotonous exercise of the arm tires, while different parts are readily employed in succession without consequent fatigue to other parts; or, what is the same thing, the arm, after being tired with one kind of work, easily performs some other task, because different muscles are called into play.* Thus the larger as well as the smaller waves of attention find their explanation on the physiological side, in the structure and arrangement of the nervous system. Also, when the current of attention is stayed, we find the reason in the absorption of the attention in certain nervous work, the correlate of which is the re-membering some fact or answering some question. [Test the above illustrations.] The differences between muscular and neural work are similarly explained. While the size of the muscles varies considerably from individual to individual, and from infancy to manhood, the brain soon ceases to grow, and varies only to a trifling extent between individual and individual.† Hence we should expect the field of attention to vary little in the individual and in different individuals, and this expectation is justified by the facts which our inquiry has elicited. The brain is also an essentially active organ, and hence we always tend to move forward. The psychology completely agrees with the neurology.

*So Foster, Physiology, part 3, 1897, §665.

+Weight of male brains: Children at birth, 330 grammes; from 1 to 2 years, 941 grammes; from 30 to 40 years, 1364 grammes; and from 70 to 80 years, 1288 grammes (Quain's Anatomy, 1893, iii, part 1, p. 178).

33.-THE FIELD OF ATTENTION.

*

What is meant by the field of attention? [Test the contents of this section.] Let us assume that we wish to lift an object. If it is but an empty matchbox on a table near by, no sensible strain is noticeable. There is no change in the field of attention as a whole, except that a portion of the total state is mechanically excerpted and made to give way as mechanically to the newcomer.* The greater the weight we have to lift, the greater the strain. Suppose we see before us on the ground a lump of iron marked "112 pounds." We wish to lift it. We have lifted weights before, and we know that much of our strength will be required for the task. Observe how we prepare.† We take a deep breath. The muscles of the body harden. The feet are firmly planted. We assume the most convenient position. We are almost a blank as far as anything but our intention is concerned. Our strength, except that absolutely required otherwise, is spent in prospectively raising the weight, or what is its equivalent. When we are about to make an unusual effort, or are making it, we abandon general thought and observation. If the weight does not demand the whole of our strength, we can lift another weight alongside of it, or we may think about other things. When the object to be moved is but a rose petal, a child may be humming a tune, skipping, and wondering about the nature of a rose petal-all at the same time. (See sec. 25.)

34.-ATTENTION ENERGY AND MOTION ENERGY ARE ONE.

What is true of muscular strain, and the consequent narrowing of the field of attention, is true of neural strain; for the two are one. We have noted how we prepare to raise a heavy weight. An exact counterpart of this is to be found in connection with ordinary attention. Suppose I think that I discern a voice in the wood. I "strain every nerve" to hear. [Test such a case.] Am I now attending? I am attending only in the same sense that I am when preparing to lift a weight. The attention is absorbed in the preparation. The brain is becoming supersensitive at certain points. Without this I should fail in my task. If other thoughts do not vanish and if labour is not concentrated, we cannot move a heavy weight, and thus when the field of attention is left unaffected, we cannot attend vigorously in a new direction. [Is that so?] The field must change as the attention becomes keen. All bodily motion, like all thought, results from organic transformations. Attention reflects but one

class of work which appears now as motion and again as sense.

We have remarked that it is not possible to distinguish between nonphysiological and physiological effort; that they are one. It will be as

*This fact, if it be one, contradicts the current theories, which imply that our condition at any moment is constituted of an indivisible organic whole.

"There is no attention without previous attention" (Ladd, Psychology, 1894, p. 77). The influence of expectancy is a favourite subject with psycho-physicists.

well to enter into somewhat greater detail. The fact usually observed in this connection is that great neural strain excludes great muscular strain (as in the dog trying to re-member), and that great muscular strain excludes great neural strain (as in lifting a heavy weight). When attention is rapt, all outward motion is suspended; and when we are engaged in severe physical work, thinking must be discarded. One fund of labour is expended in one direction, be it of thought or of action, of brain or of muscle. This might be disputed on the ground that a man may be strong in muscle, while his neural powers are indifferent. Thus it is, for instance, rightly contended that muscle training, as such, no more strengthens the nervous system than neural training, as such, strengthens the muscles. The distinction is, however, illusory, for what is true as between neural and muscular activity, is equally true within these two departments. As I attend with ease to an elaborate piece of music, and am perhaps helpless when it is a question of grappling with a mathematical demonstration, so I can be physically strong and effective in one direction, and weak and ineffective in another. Assuming the normal state, the slightest muscular effort interferes as truly with neural effort as the greatest, and vice versa, just as any neural or muscular exertion in one direction tells respectively on neural or muscular effort in every other direction. [Is this not too sweeping?]

The analogies between these two kinds of effort are numerous and instructive. We have already observed that in both spheres we can be strong or effective at one and the same time in a few directions only. We add that great strength or effectiveness in one direction is normally excluded in both departments unless we are healthy in every way. In physical exertion, too, strenuous exercise plays the same part as in neural exertion. In the former, as in the latter, the output of labour must be measured by effectiveness, and not by felt strain. Thus, again, certain

parts of the body may be tired, while others are not. These various correspondences suggest a common cause, for they are far from being superficial or accidental.

Men often learn that, after practice, they frequently perform a muscular act in spite of themselves. Thus wishing to raise my eyelids for the purpose of removing a speck of dust from the eye, I meet at first with stubborn resistance on their part. [Repeat this experiment.] Again, as physiological acts are attempted more and more frequently, so we often lose control over them. In a similar way, control in matters intellectual becomes frequently impossible, trains of thought continually passing across the stage with apparently no volition preceding them. All that we are entitled to conclude in such cases of uncontrolled activity is that changes are readily initiated in those directions. Involuntariness of actions offers no ground for a division between neural and muscular activity. Apparent unconsciousness of activity, ease and readiness of activity, independence and continuousness of activity, hold good as much in the muscular realm as in the neural, as might be proved by a profusion of examples, and these

states can, therefore, not be considered as distinguishing neural from muscular activity. Waking during the night, I am unable to dismiss an absurd dream; having seen a loathsome sight, I am unable to banish the surviving image; having felt strongly, I am unable to calm myself; laughing, I am unable to regain serenity; thinking intently of a subject for some time, I am unable to dismiss it; being tempted I cannot resist ; etc., etc. [Test these assertions.] The chief instances are perhaps supplied by our general habits which are yet so little known even to the specialist observer (ch. 3).

35.-ATTENTION AND HEREDITY.

The general nature of human activity-the mould into which it is castis determined by the organism we inherit. We readily attend. There is no need for schools where we shall be taught to distinguish, to see, to act. This power, on the whole, the organism takes over from the past. We spring into life, as regards the building up of the inner and outer world, as Minerva sprang from the head of Jove-armed from head to foot, though the equipment differs with different species of animals. The infant pigeon employs its wings to regain equilibrium; the kid jumps about and is frolicsome, unlike its adult parent; the chicken flies up to escape a rat; the gosling placidly rests in the shallow basin full of water. Again, our customary movements are so complex that, apart from predisposition, we could not have learnt them. Uninstructed attention in this wise performs that which years of elaborate training could not accomplish, while education only enables us to avoid a little friction here and there. Our acquired activity, compared with that inherent in the organism from birth, is like that of the shopkeeper who polishes and arranges his newly arrived goods, education being to heredity what the individual is to the race. The same stimuli occasion the child or young animal to spend energy in varying grooves of action. The discharge of energy, in one instance as in the other, is along certain well-established lines. No one who has closely watched the development of a human being can escape being struck with the large proportion of wisdom which the new-born child brings with it. [The advanced student should keep a record of the development of some child.] An infant is not a piece of clay, and what tuition does, is as nothing compared to what the child knows and does without tuition. Apart from the child's latent powers, and its magnificent nervous system ready to develop, it would be as little amenable to education as a snow-man. The full-grown person, too, is mostly himself and acquires from others little which is fundamental. The very depths of his being he has brought with him, his special impressibility being the result of his special organisation. What is easily admitted as being true of muscular activities is equally true of neural activities. Here also study shows that acquirements constitute an insignificant fraction of

"The twilight that sends the hens to roost sets the fox to prowl, and the lion's roar which gathers the jackals scatters the sheep" (Ward, Psychology, 1886, p. 42, col. 2).