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

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?'

Our brains are designed to arrive at an accurate picture of the world, and to use that accurate picture to act on the world effectively, at least overall and in the long run. The same computational and neurological capacities that let us make discoveries about physics or biology also let us make discoveries about love.

In fact, our brains are most active, and hungriest, in the first few years of life. Even as adults, our brains use a lot of energy: when you just sit still, about 20 percent of your calories go to your brain. One-year-olds use much more than that, and by four, fully 66 percent of calories go to the brain, more than at any other period of development. In fact, the physical growth of children slows down in early childhood to compensate for the explosive activity of their brains.

It’s not that children are little scientists but that scientists are big children.

Animals are certainly more sophisticated than we used to think. And we shouldn’t lump together animals as a group. Crows and chimps and dogs are all highly intelligent in very different ways.

It’s turns out to be much easier to simulate a grandmaster chess player than it is to simulate a 2-year-old.

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.

The very best outcome is that our children will end up as decent, independent adults who will regard us with bemused and tolerant affection; for them to continue to treat us with the passionate attachment of infancy would be pathological. Almost every hard decision of child-rearing, each tiny step – Should I let her cross the street? Can he walk to school yet? Should I look in her dresser drawer? – is about how to give up control, not how to increase it; how to cede power, not how to gain it.

Love doesn’t have goals or benchmarks or blueprints, but it does have a purpose. The purpose is not to change the people we love, but to give them what they need to thrive. Love’s purpose is not to shape our beloved’s destiny, but to help them shape their own. It isn’t to show them the way, but to help them find a path for themselves, even if the path they take isn’t one we would choose ourselves, or even one we would choose for them. The.