The idea that people are separated by only six degrees sounds too simple to be true, but it seems to hold. In the sixties psychologist Stanley Milgram asked people to send a letter to a stranger via someone they knew. On average, it took six people for the letter to reach its goal. A similar experiment was done in 2002 by sociologist Duncan Watts on a global scale using email, with the same result. And by 2010 with social media such as Facebook, we are all connected. From Death of Homo Economous