Nicholas A. Christakis

We are, first of all, not solitary creatures and second of all, we are deeply embedded in the lives of others. It's very easy to forget that and to engage in an atomistic fallacy - where we think that all we have to do is study the individual components of a system in order to understand the system.

I'm not suggesting that social scientists stop teaching and investigating classic topics like monopoly power, racial profiling and health inequality. But everyone knows that monopoly power is bad for markets, that people are racially biased and that illness is unequally distributed by social class.

We're not just social animals in the conventional way that people think. It's not just a bunch of us who hang out together. We have a very specific pattern of ties, and they have a particular shape and structure that is encoded in our genes. It means that human beings have evolved to live their lives embedded in social networks.

We exist in this weirdly schizo culture, where sex is everywhere in the media, and yet, at the same time, you don't sit down and have a conversation about what you did in bed last night with your friends. Despite the ubiquity of sex, it's still a taboo when it comes to day-to-day conversation.