The "terrible 2s" are worse than we knew. Research is showing that for almost every little boy (or girl) such as Maxim, not even a rocky adolescence will come as close to the rapid-fire tantrums of the toddler years.

Researchers argue that society must stop excusing aggression in early childhood. Ignoring the problem could mean a child's path is set irrevocably toward delinquency, dropping out of school, and crime. Intervention, it seems, needs to come sooner than ever. If aggressive children don't learn to control their anger early, they might never learn at all.

The idea requires adults to face the worst of human nature in their own children -- that bad things can come in small packages. It goes straight to the age-old debate about the origins of evil: Are human beings born pure, as Rousseau argued, and tainted by the world around them? Or do babies arrive bad, as St. Augustine wrote, and learn, for their own good, how to behave in society?

Richard Tremblay, an affable researcher at the University of Montreal who is considered one of the world leaders in aggression studies, sides with St. Augustine ...