Essentially, we humans live well enough and long enough, and are smart enough, to generate all sorts of stressful events purely in our heads.

Importantly, rather than promoting aggression, testosterone promotes whatever is needed to maintain status when challenged.

...I might continue to believe that there is no god even if it were proved that there is. A religious friend of mine once remarked that the concept of god is useful, because you can berate god during the bad times. But it is clear to me that I don't need to believe there is a god in order to berate him.

The regulation of genes is often more interesting than the genes themselves, and it's the environment that regulates genes.

Pulling a gun's trigger can be an appalling act. But if it is suicidal drawing fire to save someone, it has an utterly different meaning. Placing your hand on someone's arm can be an act of deep compassion or the first step of betrayal. The punch line? It's all about context, and the biology of context is vastly more complicated than the biology of the behavior itself.

I love science, and it pains me to think that so many are terrified of the subject or feel that choosing science means you cannot also choose compassion, or the arts, or be awed by nature. Science is not meant to cure us of mystery, but to reinvent and reinvigorate it.

What does the frontal cortex do? Gratification postponement, executive function, long-term planning, and impulse control. Basically, it makes you do the harder thing.