Individual differences in testosterone level predict very little about differences in aggression.

The frontal cortex is an incredibly interesting part of the brain - ours is proportionately bigger and/or more complex than in any other species.

What happened in the milliseconds before a behavior to cause it? That's in the neurobiological realm.

We all seek out stress. We hate the wrong kinds of stress but when it's the right kind, we love it - we pay good money to be stressed by a scary movie, a roller coaster ride, a challenging puzzle.

If you live in a baboon troop in the Serengeti, you only have to work three hours a day for your calories, and predators don't mess with you much. What that means is you've got nine hours of free time every day to devote to generating psychological stress toward other animals in your troop. So the baboon is a wonderful model for living well enough and long enough to pay the price for all the social-stressor nonsense that they create for each other. They're just like us: They're not getting done in by predators and famines, they're getting done in by each other.

The most important point of [Susan] Fiske's work is that it provides a taxonomy for our differing feelings about different Thems - sometimes fear, sometimes ridicule, sometimes contemptuous pity, sometimes savagery.

Oxytocin is a Teflon hormone - bad news rolls off it.