Childhood is a fundamental part of all human lives, parents or not, since that's how we all start out. And yet babies and young children are so mysterious and puzzling and even paradoxical.

Babies and young children are like the research and development division of the human species, and we grown-ups are production and marketing.

Asking questions is what brains were born to do, at least when we were young children. For young children, quite literally, seeking explanations is as deeply rooted a drive as seeking food or water.

Young children seem to be learning who to share this toy with and figure out how it works, while adolescents seem to be exploring some very deep and profound questions: 'How should this society work? How should relationships among people work?' The exploration is: 'Who am I, what am I doing?'

From an evolutionary perspective children are, literally, designed to learn. Childhood is a special period of protected immaturity. It gives the young breathing time to master the things they will need to know in order to survive as adults.

The swashbuckling independence of my childhood was not all good, and as a father, I'm puzzling out how to be part of my children's lives rather than shoehorning them into mine. But there's a risk that I'll overcompensate, of course.