It's fashionable to speak about vulnerable populations in medicine and public policy, but it's harder to find a more vulnerable population than those who are dying.

One reason citizens, politicians and university donors sometimes lack confidence in the social sciences is that social scientists too often miss the chance to declare victory and move on to new frontiers.

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

We discovered that if your friend's friend's friend gained weight, you gained weight. We discovered that if your friend's friend's friend stopped smoking, you stopped smoking. And we discovered that if your friend's friend's friend became happy, you became happy.

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.

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.

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.