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

As with real reading, the ability to comprehend subtlety and complexity comes only with time and a lot of experience. If you don't adequately acquire those skills, moving out into the real world of real people can actually become quite scary.

The vexing thing about human behavior is that when we say we know we should do something, we really and truly do know it. It's hard to be 50 lbs. overweight or smoke a pack a day or feel miserable every moment you spend at work and not understand in a deep and primal way that change is in order - and that in some cases it could even save your life.

I was born in the U.S., my wife was born in Mexico and emigrated here when she was in college, and my daughters were born in New York City. That makes them passport-carrying, natural-born, eligible-to-run-for-president Americans. But they're also Mexicans and they like that just fine.

There are a lot of ways to make people not like you, but one of the most powerful - if least fair - is to be really, really successful. Nobody resents the guy who just lost his job. But the guy whose Internet start-up made him a billionaire at 25? That's a whole different kettle of envy.

The mind and the body are inextricably entwined, and rarely are their inseparability clearer than when we're under some kind of mental pressure. The moment we start trying to learn a new skill, make a decision or otherwise think on our feet, our nervous system reacts - with accelerated pulse rate, increased respiration, even sweating.

Spending $1 for a brand new house would feel very, very good. Spending $1,000 for a ham sandwich would feel very, very bad. Spending $19,000 for a small family car would feel, well, more or less right. But as with physical pain, fiscal pain can depend on the individual, and everyone has a different threshold.