Romantic love is an addiction.

Romantic love is not an emotion. ... It's a drive. It comes from the motor of the mind, the wanting part of the mind, the craving part of the mind.

From my studies of genetics and neuroscience I have come to believe that people fall into four broad personality types - each influenced by a different brain chemical: I call them the Explorer, Builder, Director, and Negotiator.

When chimps threaten, they open their mouth and show their teeth. It's a little like waving a knife in front of you. It's very primitive, and therefore bizarre.

We still have community, but we don't seem to have local community. Even in a small town where you know your neighbors and your mother's down the street, they're not in arm's length.

Women have a better sense of smell than men do, and it's even sharper in the middle of their menstrual cycle, when estrogen levels peak and women are more likely to be deciding whether a man's attractive.

Any kind of novelty or excitement drives up dopamine in the brain, and dopamine is associated with romantic love.