We adults do not commonly understand boys. Half of us, to be sure, were boys ourselves; but when we became men and settled down to our work, we did not merely put away childish things—we went further and forgot them. To-day, we read a story of boy life and we say, “Why, yes. That’s just the way boys do. I used to do exactly that sort of thing myself.” But the next hour we have forgotten again, and the boy we were is once more a stranger. Boyville is so far removed, both from Delos and from Babylon, that we seldom think the thoughts of its inhabitants, nor see the world with the boys’ eyes. Only a few men are at home in both worlds,—Lindsay, George, some schoolmasters, an occasional father,—and these can do anything with a boy. The difficulty seems not so much to be that we have forgotten the incidents of our boyhood as that we have lost its feelings. So far as specific doings are concerned, we probably remember those crowded years more distinctly than any equal period of our entire lives. Most of us, too, remember them happily, as happily probably as any years we have lived. No, the trouble is not with the memory, but with the self. The experiences of life since we were boys have shifted our psychic centre of gravity, so that we realize the particular incident far more easily than we realize the being to whom it occurred. We do not completely feel that the boy that was is quite ourselves; and while the memory of the fact is sharp, the memory of the mental state that went with it has become dim. Therefore, it costs a distinct effort to put one’s self in the boy’s place. Any proper man will recite by the hour tales of the old swimming-hole in the summer. But if men actually felt toward the water as boys do, every club and half the private houses would have a swimming tank instead of a smoking room. But if we men fail to comprehend boys, what shall we say of the women! The experiences which we have forgotten, they have not even had; if there is a psychic fence which separates men from boys, there are at least knot-holes in the boards; but between boys and women there is a solid wall. There are parts of a boy’s soul which any woman may observe or imagine, but which no woman can ever feel. That women often do understand boys, understand them sometimes better than men do, is simply one of the marvels of feminine insight.

This book is, then, addressed, first of all, to fathers, with the hope that it will, in some sort, serve to revive memories of boyhood days, not so much of specific acts of boyhood as of long-dead impulses and past ways of envisaging the world. Every man who sits down and thinks out for himself, not only what he did as a boy, but also how it feels to be a boy, and how the world and the people in it appear through a boy’s eyes, has taken a long step toward the understanding and the control of his own sons. A scientific account of certain aspects of boy psychology, such as this book aims to be, may aid this introspective process.

On the other hand, so far as this book is an account of the natural history of the genus boy, it may well be an aid to mothers, and to other women who, with no children of their own, are yet concerned for the welfare of adolescent males. If it does not help these to a sympathetic understanding of a boy’s soul, one may at least hope that it will serve to warn them of those regions of it most foreign to their sex. Next to a knowledge of boy nature, comes the knowledge of when to keep hands off and let some man have his chance. To the smaller group of women, mothers and aunts and elder sisters, and especially teachers, who already possess the heaven-sent gift of understanding boys, any assistance may well seem superfluous. Still, intuition may often be supplemented by science. The clearest insight does sometimes fail, and need to be helped out by a more analytical approach from another side than its own. To men, women, and teachers, then, this book,—an ‘apology,’ in a sense, to women, of men who once were boys.

Whoever it was that opined that

knew little about boys. The child becomes a youth, and the youth becomes man, by virtue of a process not so very different from that which transforms the caterpillar into a butterfly or the tadpole into a frog. As truly as the caterpillar takes on wings, and the tadpole lungs and limbs, of which neither had any trace before, the child and the boy take on not only habits and instincts and ways of getting on in the world, but actual new structure as well. Boyhood begins with the second set of teeth; it ends with the advent of the beard and a new set of enzymes in the blood. Neither child nor boy nor grub nor pollywog passes on to the next stage of his existence by any mere enlargement.

Nor is it altogether true that with the approach of manhood

The little child, in his father’s house and under his father’s care, feels the stir of newborn gregarious instincts, and takes his first steps into the larger life of the world. Boyhood proper begins with the rise of impulses which make us citizens and lead us to take care of ourselves; and it ends with the rise of impulses which make us heads of families and lead us to take care of other people. Each step is an enlargement of life. Each transition is marked by a psychic change so profound that it makes the previous narrower condition appear as shadowy almost as a dream, and almost as difficult to recall.

We are concerned here with the second of the seven ages of men: with the period, that is, which begins at about the age of ten with the rise of the herding instincts, and ends with the rise of the mating instincts at, say, eighteen. The child, who thus far has been a solitary animal, suddenly becomes a social one. He is profoundly interested in youth of his own sex, while at the same time he cares less than nothing for youth of the other. Therefore, he associates himself with other boys and forms gangs.

The gang, therefore, while it lasts, is for the boy one of the three primary social groups. These three are, the family, the neighborhood, and the play group; but for the normal boy the play group is the gang. All three are instinctive human groupings, formed like pack and flock and hive, in response to deep-seated but unconscious need. Like all such instinctive associations, the gang appears useless or stupid to those who have never felt the inner impulse which caused it, or who, having felt, have forgotten. The boy’s reaction to his gang is neither more nor less reasonable than the reaction of a mother to her babe, the tribesman to his chief, or the lover to his sweetheart. All these alike belong to the ancient, instinctive, ultra-rational parts of our human nature. They are felt, and obeyed; but only in part are they to be explained, for no man understands any of them fully unless he knows how it feels from the inside.