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

There's the complex categorization of low warmth/high competence. This is the hostile stereotype of Asian Americans by white America, of Jews in Europe, of Indo-Pakistanis in East Africa, of Lebanese in West Africa, of ethnic Chinese in Indonesia, and of the rich by the poor most everywhere. It's the same low-high derogation: They're cold, greedy, clannish - -but, dang, they're sure good at making money and you should go to one who is a doctor if you're seriously sick.

But if you get chronically, psychosocially stressed, you're going to compromise your health. So, essentially, we've evolved to be smart enough to make ourselves sick.

We are just another primate but a very confused, malleable one.

Finish this lecture, go outside, and unexpectedly get gored by an elephant, and you are going to secrete glucocorticoids. There's no way out of it. You cannot psychologically reframe your experience and decide you did not like the shirt, here's an excuse to throw it out - that sort of thing.

What happened during the minutes before? That's the realm of sensory stimuli of the nervous system.

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.