You size up someone physically in less than one second - too tall, too short, too fat, too thin, too old, too young, too stuffy, too scruffy.

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

When you massage someone, the levels of oxytocin go up in the brain, and oxytocin is one of the chemicals that drives attachment.

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

Whether you're married or not, relationships - and the satisfaction tied to them - are extremely important for increasing men's and women's quality of life.

Today, American women bear an average of 2.2 children that live to adulthood. Across most of Europe, women bear even fewer young.

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.