For the explanation why only three in every four boys are in gangs, instead of four in every four, is largely that the fourth boy is one whom the gang will not have. Some boys, of course, are solitary by nature,--sensitive, retiring boys who do not care for the rough life of the gang, but prefer to play alone, with one companion, or with girls. Some, too, grow up in isolated neighborhoods where there are few other boys of the same age. These lose, perforce, the education that comes in the gang. But the rest who stay out of the gang, stay out for the gang’s good. They have been trained, often against their nature, to do violence to the gang’s standard of honor. They fail to pass through the normal development of human males; they lack a fundamental virtue and their fellows will not trust them, boy or man. In the gang, then, we find the natural time and place for the somewhat sudden birth and development of that spirit of loyalty which is the foundation of most of our social relations. We must, in short, look upon the gang as nature’s special training-school for the social virtues. Only by associating himself with other boys can any youth learn the knack of getting on with his fellow men; acquire and practice coöperation, self-sacrifice, loyalty, fidelity, team play; and in general prepare himself to become the politician, the business man, the efficient citizen of a democracy. Nature, we must believe, has given the boy the gang instincts for the sake of making easy for him the practice of the gang virtues. It may well be questioned whether any association of state or church or neighborhood or school or order has had a greater influence over the lives of most of us men than had the dozen or so of boys who were our intimate companions between the ages of twelve and fifteen. We must not forget that the instinctive vices of the gang tend largely to be self-limiting, so that the boy, even if left entirely alone, would outgrow most of his faults. Not so with the gang virtues. The impulses to loyalty, fidelity, coöperation, self-sacrifice, justice, which are at the basis of gang psychology, are powerfully reinforced, as we have already seen, by nearly all the typical gang activities. Even collective stealing is a lesson in coöperation. Thieving expeditions are often definitely planned; one boy watches while the others steal; one engages the attention of the storekeeper while another annexes his property; one member of the gang plagues the victim to get chased, and then the rest loot his goods. Most especially, however, in the group games of the gang do we find the most convenient tool for teaching many of the most essential social qualities. “In playing group games,” says Joseph Lee, “morality is being born and the social man, man the politician, man the citizen; and it is my belief that in most instances this political or social man will get himself thoroughly and successfully born in no other way.”