Behave: The Biology of Humans at Our Best and Worst

To use the feeble joke told to first-year medical students, the SNS mediates the “four Fs—fear, fight, flight, and sex.”

the result is more oxygen and glucose for the muscles.

with the usual advantages and disadvantages of categorizing a continuum.

Which reminds us that we don’t hate aggression; we hate the wrong kind of aggression but love it in the right context.

The opposite of love is not hate; its opposite is indifference

Can you ever separate doing good from the expectation of reciprocity, public acclaim, self-esteem, or the promise of paradise?

Then there’s another version of “This isn’t personal”—targeting someone just because they’re weak and you’re frustrated, stressed, or pained and need to displace some aggression.

While a few other species have regular nonreproductive sex, we’re the only ones to talk afterward about how it was.

we use the same muscles as does a male chimp attacking a sexual competitor, but we use them to harm someone because of their ideology.

When it’s the “right” type of aggression, we love it.