When should you unfriend someone on Facebook?

Alexis Elder is an assistant professor of philosophy at the University of Minnesota Duluth.  Her book, Friendship, Robots and Social Media False Friends and Second Selves, has just hit the shelves. Everyone has an overly political or opinionated friend on Facebook or the friend that shares too much about his or her children.  Is it okay to unfriend people who don’t have the same opinions as us? Is Social Media bringing us closer together or tearing our friendships apart? Alexis Elder, a professor of philosophy at the University of Minnesota Duluth, explains when to unfriend.