There is another way in which the development of the humorous faculty enlarges the sphere of the risible. In the simple nature of children and uncultured adults, fun and seriousness tend to dwell apart. The introduction of a serious element into the mood of amusement, which is at the basis of humour, makes a breach in the dividing wall. As a consequence, the humorist, though a profoundly serious person, will show a readiness in the midst of grave occupations to digress for a moment at the prick of some ludicrous suggestion. Good talkers and letter-writers, including women with the quick ear for the bubblings of fun, are thus given to momentary interruptions of serious discourse by side-glances at amusing aspects, and many persons who take themselves to be humorists are apt to be shocked at {320} the proceeding. Yet, in truth, the extent to which a man succeeds in making laughter permeate the sphere of the serious, without loosening its deep-laid foundation of gravity, is one of the best measures of the vitality of his humour. It is this resolute yet perfectly respectful invasion of the domain of the serious by humour which has made a good deal of modern literature possible. Of this, more anon: it may suffice for the present to call attention to a work of a friend of mine dealing with a subject which might well seem to be dismally serious—logic itself, a work which attempts with conspicuous success, while maintaining the dignity of the science, to relieve its heaviness by a good number of amusing remarks and illustrations.[275] Yet the expansion of the range of enjoyment when mindless mirth gives place to humour is not wholly due to the absorption of a serious element. One chief limitation of the more common kind of laughter arises from the circumstance that it is apt to be disagreeable to the person who is its object. This dislike, again, is due, as we have seen, to a natural feeling of resentment at being taken down and treated as an inferior. So long as the laughter retains a distinct vibration of the old note of contempt, we must resist it; but when it grows mellow and kindly we are ready to withdraw the objection. There is nothing so terrible in having fun poked at our foibles, or even at our petty misfortunes, so long as we know that a friendly face is hiding behind the laughing mask. If a person only gives the assurance in his way of laughing that contempt is drowned in a more genial sentiment, he may laugh at his children, aye at his parents, too, even when they grow old and infirm. Nor is a previous knowledge of friendly disposition always needed. There are a few whose mellow {321} laughter will instantly disarm resistance in a stranger—in the street boy, for example, though he has the double sensitiveness of the poor and of the young.