An adult man’s interests are almost every one of them intensely artificial: they have slowly been built up. The objects of professional interest are most of them, in their original nature, repulsive; but by their connection with such natively exciting objects as one’s personal fortune, one’s social responsibilities, and especially by the force of inveterate habit, they grow to be the only things for which in middle life a man profoundly cares.
But in all these the spread and consolidation have followed nothing but the principles first laid down. If we could recall for a moment our whole individual history, we should see that our professional ideals and the zeal they inspire are due to nothing but the slow accretion of one mental object to another, traceable backward from point to point till we reach the moment when, in the nursery or in the schoolroom, some little story told, some little object shown, some little operation witnessed, brought the first new object and new interest within our ken by associating it with some one of those primitively there. The interest now suffusing the whole system took its rise in that little event, so insignificant to us now as to be entirely forgotten. As the bees in swarming cling to one another in layers till the few are reached whose feet grapple the bough from which the swarm depends; so with the objects of our thinking,—they hang to each other by associated links, but the original source of interest in all of them is the native interest which the earliest one once possessed.
Whoever treats of interest inevitably treats of attention, for to say that an object is interesting is only another way of saying that it excites attention. But in addition to the attention which any object already interesting or just becoming interesting claims—passive attention or spontaneous attention, we may call it—there is a more deliberate attention,—voluntary attention or attention with effort, as it is called,—which we can give to objects less interesting or uninteresting in themselves. The distinction between active and passive attention is made in all books on psychology, and connects itself with the deeper aspects of the topic. From our present purely practical point of view, however, it is not necessary to be intricate; and passive attention to natively interesting material requires no further elucidation on this occasion. All that we need explicitly to note is that, the more the passive attention is relied on, by keeping the material interesting; and the less the kind of attention requiring effort is appealed to; the more smoothly and pleasantly the classroom work goes on. I must say a few more words, however, about this latter process of voluntary and deliberate attention.