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

All of us gardeners know that nothing comes out the way you planned. It's a different garden every year, and it's always sort of different from what you were thinking when you began. What it really means to be a good gardener is to work hard to produce an ecosystem that will have enough diversity, enough possibilities, so it's robust, and it's resilient, and it can change when the seasons change. And that kind of robust, unexpected, variable, messy system - that's what you want to create when you're having children, too.

The more obsessively we focus on what a particular food is going to do for us, the less healthy we've become. Simple pleasures become complicated.

We pass our values, ideas and moral character on to our children, but we do that knowing that our children are going to revise our knowledge and reshape their values. There's something very paradoxical and profound about being a parent as opposed to parenting. We put in all this effort and energy not so that we can shape a child of a particular sort, but so that all sorts of possibilities can happen in the future.

Adults often assume that most learning is the result of teaching and that exploratory, spontaneous learning is unusual. But actually, spontaneous learning is more fundamental.

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.

Ineffective or weak brain connections are pruned in much the same way a gardener would prune a tree or bush, giving the plant a desired shape.