The frontal cortex doesn't even fully develop until age 25, which is wild!

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.

To out-group-members, oxytocin makes you crappier - less cooperative and more preemptively aggressive. It's not the luv hormone. It's the in-group parochialism/xenophobia hormone.

The problem isn't testosterone and aggression; it's how often we reward aggression. And we do: We give medals to masters of the "right" kinds of aggression. We preferentially mate with them. We select them as our leaders.

Depression is not generalized pessimism, but pessimism specific to the effects of one's own skilled action.

Get it wrong, and we call it a cult. Get it right, in the right time and the right place, and maybe, for the next few millennia, people won't have to go to work on your birthday.

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.