The fascinating thing about our best and worst behaviors isn't the behavior itself - the brain tells the muscles to do something or other - big deal. It's the meaning of the behavior.

It's probably even the case that if you stoked up some Buddhist monks with tons of testosterone, they'd become wildly competitive as to who can do the most acts of random kindness.

Most of us don't collapse into puddles of stress-related disease.

Almost always, genes are about potentials and vulnerabilities rather than about determinism.

Stress is not a state of mind... it's measurable and dangerous, and humans can't seem to find their off-switch.

Brains distinguish between an Us and a Them in a fraction of a second. Subliminal processing of a Them activates the amygdala and insular cortex, brain regions that are all about fear, anxiety, aggression, and disgust.

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