At the beginning of this book, it was noted that serious antisocial behavior seldom seems to develop in children unless there is a convergence of a number of predisposing and precipitating factors. Constitutional factors may predispose the individual to respond aggressively, but children's interactions with their environment during their development and the lessons they learn from these interactions are probably more important determinants of human aggressiveness. No one can expect anyone factor by itself to explain which child becomes a very aggressive adult and which child does not. However, when certain cognitive, familial, and environmental characteristics occur in conjunction, aggressive behavior becomes much more likely in a child.