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

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.

We and others have done a bunch of work to show that if your real friends online say or do something, it affects you. But if your acquaintances online say or do something, it does not. People on average have about 106 Facebook friends, but only 5 or 6 real friends.

Nicholas A. Christakis Quotes