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.

Anthropologists have found evidence of romantic love in 170 societies. They've never found a society that did not have it.

Real competition can drive up testosterone, which boosts libido.

I can't conceive of caring more about my president than my own partner.

Kissing is not just kissing. It is a major escalation or de-escalation point in a powerful process of mate choice.

People have often asked me whether what I know about love has spoiled it for me. And I just simply say, 'Hardly.' You can know every single ingredient in a piece of chocolate cake, and then when you sit down and eat that cake, you can still feel that joy.

Any time you choose not to hide your tattoo, you're limiting your social sphere, because they're not popular in big business.