(2) We pass to the question of the various forms or kinds of attention. It may he said at once that there is but one attention. The essen tial features of the attentive state are, always and everywhere, as we have just described them. The differences between one bit of attentive ex perience and another are differences, first, in the determination or motivation of attention; and secondly, in the sense-processes which are set up by the attentive attitude. We deal now with the determinants of attention. (a) There are certain stimuli and forms of stimuli which com mand our full and immediate attention. Thus, very intensive stimuli compel us to pay regard to them. However interesting our novel may be, we shall start up, automatically and unhesitat ingly, if a gun is fired outside of the window of our room. We have no choice but to attend to the sudden, loud sound. Intensity, suddenness, novelty, movement—all these properties of stim uli are attention-compelling. The moving bird that flits across the landscape; the moving voice that rises and falls to the more stationary or chestral accompaniment; the moving stimulus in the field of touch—these things hold our at tention whether we will or no. There is good physiological reason for the power of such stim uli, inasmuch as all alike are fitted by their attention - compelling properties to exert a marked influence upon nervous substance. There is also good biological reason for their efficacy. An• animal so constituted as to leave unnoticed the sudden and novel and moving features of its surroundings would soon pay the forfeit of its neglect with life. This 'primary passive atten tion,' or 'involuntary attention.' is. then, a heritage from earlier and less secure conditions of living. Our ancestors could not have survived without it, and it persists, ingrained in our nervous constitution, even though in civilized communities the reason for its continuance has largely disappeared. (b) This single and master ful determination of attention, however, cannot persist unchanged. The organism grows in com plexity; its sense-organs multiply. And this means that there may be rival claimants, so to speak, for the favor of attention. Suppose that eye and ear are simultaneously called upon—the eye by a moving object in one direction, the ear by an intensive sound proceeding from a differ ent quarter. There will, evidently, be doubt and conflict, of a piece with the doubt and conflict that are set up by the occurrence of a number of potential motives to selective action. (See Aci Trox.) Furthermore, as the retrospective lime tions develop, and the mind is stocked with memories, each of the would-be determinants of attention will form a centre of association; ideas will cluster round it, some to help and some to hinder. So we reach the stage of `active' or 'voluntary attention'—the sort of attention that we give to a new game of skill that we are learning or a new problem that we are seeking to solve. There the attention is divided; no single set of ideas receives a full measure of it; there is effort and struggle and misdirection of energy. Again, however, atten tion cannot persist, unchanged, at this i.evel.
If the struggle be continued active attention passes, inevitably, into (c) 'secondary passive attention.' dust as the selective action slips back, with repetition, into a secondary reflex, so does active attention presently fall under the exclusive dominance of some one of the rival determinants. We begin the novel voluntarily, in face of conflicting duties. As we read we grow absorbed in the story. What is this 'absorp tion' but a reappearance of primitive attention upon a higher plane of mental development? The attention-compelling property of the successful stimulus is no longer intensity or novelty, but something much more subtle. It is the relation of the stimulus in question to the whole content of consciousness. As soon as our mind is set for the plot of the norel, and all intruding ideas have been banished, the incidents, as they come, have full sway over us; we are prepared for them, ready to receive them: they fit in with our mental trend and tendency. Every trained mind is thus dominated by the objects which appeal to its training; the poet, by works of the creative imagination; the physician, by the de tails of a new treatment; the painter, by an effect of color upon the landscape; the zoiilogist, by the forms of animal life. We can never transcend the dictates of the primary passive attention ; the most absorbed reader, the most abstracted thinker, starts at the sound of the gun. But our intellectual life, when it has reached the stage of achievement, is in the main a life of secondary passive attention. From the educational point of view the stage of active attention is a stage of waste, of non-attainment; mastery comes with secondary passive attention. But, then, there is no road to this last save through active attention: work comes before The child must be led to work in order that his play, in adult life, may be of the highest possible service to society.
(3) Little need be said of the sense-processes that are aroused by the bodily attitude of atten tion, the strains and vressures that come to consciousness from eye or ear, as the attention is visually or auditorily directed. Some psy chologists, envisaging attention as a purely motor phenomenon, have laid much stress upon these muscular adjustments; and there can be no doubt that they help to induce and to main tain the attentive state. But while this is true, it seems to be equally certain that the sensations which proceed from the adjustments are merely secondary characteristics of the attentive con sciousness. As Kuelpe puts it, they are con secutive, not constitutive. They contribute largely to the experience of effort in active atten tion. And it is interesting to notice, as Fechner and James have done, the change of direction which this effort undergoes, according as the object of attention belongs to the world of things or to the world of thought. In the former case it is a straining outward ; in the latter, a strained retraction or withdrawal inward. Further study of the sensations, however, throws no new light upon the mechanism of attention.