Liberty is the experimental condition for studying the phenomena of the child's attention. It will be enough to remember that the stimuli of infant attention, being mainly sensory, have a powerful physiological concomitant of "accommodation" in the organs of sense; an accommodation, physiologically incomplete in the young child, which requires to develop itself according to Nature. An object not adapted to become a useful stimulus to the powers of accommodation in process of development would not only be incapable of sustaining attention as a psychical fact, but would also, as a physiological fact, weary or actually injure the organs of accommodation such as the eye and ear. But the child who chooses the objects, and perseveres in their use with the utmost intensity of attention, as shown in the muscular contractions which give mimetic expression to his face, evidently experiences pleasure, and pleasure is an indication of healthy functional activity; it always accompanies exercises which are useful to the organs of the body.
Attention also requires a preparation of the ideative centers in relation to the external object for which it is to be demanded: in other words, an internal, psychical "adaptation." The cerebral centers should be excited in their turn by an internal process, when an external stimulus acts. Thus, for instance, any one who is expecting a person, sees him arriving from a considerable distance; not only because the person presents himself to the senses, but because he was "expected." The distant figure claimed attention because the cerebral centers were already excited to that end. By means of similar activities a hunter is conscious of the slightest sound made by game in woods. In short, two forces act upon the cerebral cell, as upon a closed door: the external sensory force which knocks, and the internal force which says: Open. If the internal force does not open, it is in vain that the external stimulus knocks at the door. And then the strongest stimuli may pass unheeded. The absent-minded man may step into a chasm. The man who is absorbed in a task may be deaf to a band playing in the street.
The central action that constitutes attention is the factor of the greatest psychological and philosophic value, and the one which has always represented the maximum among the practical values in pedagogy. The whole art of teachers has consisted, in substance, in preparing the attention of the child to make it expectant of their instruction, and in securing the cooperation of those internal forces which should "open the door" when they "knock." And as the thing which is quite unknown, or that which is inaccessible to the understanding, can awaken no interest, the fundamentals of the art of teaching were to go gradually from the known to the unknown, from the easy to the difficult. It is the preexistent "known" which excites expectation and opens the door to the novel "unknown"; and it is the already present "easy work" which opens new ways for penetration, and puts the attention into a state of expectation.
Thus, according to the conceptions of pedagogy, it should be possible to "prepare good offices for oneself," the cooperation of the psychical concomitants of the attention. Everything would depend on skilful manipulation between the known and the unknown and similar things: the clever teacher would be like the great military strategist, who prepares the plan of a battle upon a table; and man would be able to direct man, leading him wheresoever he pleases.
This, moreover, has long been the materialistic principle which governs psychology. According to Herbert Spencer, the mind is at first, as it were, an indifferent day, on which external impressions "rain," leaving traces more or less profound. "Experiences" are, according to him and the English empiricists, the constructive factors of the mind even in its highest activities. Man is what experience has made him; hence, in education, by preparing a suitable structure of experiences, it is possible to build up the man. A conception not less materialistic than that which presented itself for a moment before the marvelous progress of organic chemistry, when the series of syntheses succeeded that of analyses. It was then believed that a species of albumen might be manufactured synthetically, and as albumen is the organic basis of the cells, and as the human ovum is nothing but a cell, man himself might one day be manufactured on the chemist's table. The conception of man as the creator of man was quickly discredited in the material domain; but the psychical homunculus still persists among the practical conceptions of pedagogy.
No chemical synthesis could put into the cell, apparently nothing more than a simple clot of nucleated protoplasm, that activity sine matter, that potential vital force, that mysterious factor which causes a cell to develop into man.
And the elusive attention of children would seem to tell us that the psychical man is subject to analogous laws of auto-creation.
The most modern school of spiritualistic psychologists, to which William James belonged, recognized, in the concomitant of attention, a fact bound up with the nature of the subject, a "spiritual force," one of the "mysterious factors of life."
"... From whence his intellect
Deduced its primal notices of thought,
Man therefore knows not; or his appetites
Their first affection; such In you as zeal
In bees to gather honey."