Marriage is a lot of things - a source of love, security, the joy of children, but it's also an interpersonal battlefield, and it's not hard to see why: Take two disparate people, toss them together in often-confined quarters, add the stresses of money and kids - now lather, rinse, repeat for the rest of your natural life. What could go wrong?

There's a deep-freeze of sorts for all good intentions - a place that you store your plans to make changes in your life when you know you're not going to make them at all.

Learning to speak was the most remarkable thing you ever did.

Humans have a fraught relationship with beasts. They are our companions and our chattel, our family members and our laborers, our household pets and our household pests. We love them and cage them, admire them and abuse them. And, of course, we cook and eat them.

We are all born with an innate understanding of interpersonal equity - the idea that if you lend me your rake today, I'll respond in kind when you come to borrow my shovel tomorrow. Or nearly all of us are born with that. Psychopaths aren't.

There's no such thing as downtime for your brain.

Introverts listen better, they assess risks more carefully, they can be wiser managers. It's not for nothing that the Silicon Valley billionaires are so often the retiring types.