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

You fall in love with somebody who fits within what I call your 'love map,' an unconscious list of traits that you build in childhood as you grow up. And I also think that you gravitate to certain people, actually, with somewhat complementary brain systems.

In America, we are demanding everything from our marriage.

Saliva has testosterone and estrogen. When you kiss, you're having a chemical experience.

Scientists know that women gravitate to men who have a different immune system from theirs.

Games are the way we keep romance alive. They're based in human hardwiring. Playing hard-to-get or leaving a little to the imagination allows the woman to be wooed and appreciated and the man to be challenged and intrigued.

There were real reasons that you were attracted to somebody originally. The brain doesn't pick willy-nilly. Unless you part ways hating each other for some reason, that mechanism could get triggered again. You can literally fall in love again.