The frontal cortex is an incredibly interesting part of the brain - ours is proportionately bigger and/or more complex than in any other species.

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.

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.

How much you groom somebody else is more important than who grooms you.

If you care about your longevity and health, be a socially affiliated baboon who is better than high-ranking ones at walking away from provocations.

But often, it's easier to resist temptation with distraction, or to be so inculcated in doing the right thing that it's automatic, outside the frontal cortex's portfolio - Then it isn't the harder thing, it's the only thing you can do.

Perhaps most excitingly, we are uncovering the brain basis of our behaviors - normal, abnormal and in-between. We are mapping a neurobiology of what makes us us.