We will create life from inanimate compounds, and we will find life in space. But the life that should more immediately interest us lies between these extremes, in the middle range we all inhabit between our genes and our stars.

My entire youth was spent with an incredibly ill parent... I don't think you can grow up that way and not be marked by that experience.

There are very fundamental reasons we live our lives in social networks and if we really understood the role they're playing in our society we would take better care of social networks and find ways to take advantage of their power to improve our society.

If your friends are obese, your risk of obesity is 45 percent higher. ... If your friend's friends are obese, your risk of obesity is 25 percent higher. ... If your friend's friend's friend, someone you probably don't even know, is obese, your risk of obesity is 10 percent higher. It's only when you get to your friend's friend's friend's friends that there's no longer a relationship between that person's body size and your own body size.

It used to be thought that our genes were historically immutable and that it was not possible to imagine a conversation between culture and genetics.

It is well to look around at whom, and not just what, surrounds us. Population structure will change everything. Our health, wealth, and peace depend on it.

People have just assumed that... if we call our Facebook acquaintances our friends, we must be influenced by them, too. But we're not.