Philosophers and psychologists have long puzzled over the question of how we know as much as we do despite our limited experiences. One way is to see how children learn. Another example is consciousness. The concept is usually explored by armchair academics. Looking at kids expands our conceptions of consciousness.

Instead of just saying, "I love my baby and I pick him up because he's adorable and it's so nice to cuddle with him," we practice attachment parenting. We let our children play outside and have age-appropriate freedoms and are labeled free-range parents.

There is a tension between our desire to get our kids to turn out a particular way versus letting them develop to be their own person. If there were a pill that would make my child turn out the way I wanted, I'm not sure I'd take it.

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.

Developmental scientists like me explore the basic science of learning by designing controlled experiments.

The youngest children have a great capacity for empathy and altruism. There's a recent study that shows even 14-month-olds will climb across a bunch of cushions and go across a room to give you a pen if you drop one.

If parents are the fixed stars in the childs universe, the vaguely understood, distant but constant celestial spheres, siblings are the dazzling, sometimes scorching comets whizzing nearby.