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.

At the root of the shy temperament is a deep fear of social judgment, one so severe it can sometimes be crippling. Introverted people don't worry unduly about whether they'll be found wanting, they just find too much socializing exhausting and would prefer either to be alone or in the company of a select few people.

When we're awake, cortisol can fragment memories - one reason eyewitness crime scene accounts are so unreliable. But at night that very fragmentation allows creative recombinations of ideas.

When our culture shifts, it tends to overcorrect, throwing out everything associated with an era we've moved past, rather than saving what was good and combining it with what is new.

The death of anti-gay hate speech is no doubt being hastened by the head-spinning speed with which gays as a group - to say nothing of gay marriage - are becoming an unremarkable and even quite traditional parts of American life.

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.

A fishnet is made up of a lot more holes than strings, but you can't therefore argue that the net doesn't exist. Just ask the fish.