We affect each other in more ways than we realize. Our influence on one another is not only what we see and measure in others—studies show that we “emotionally infect” one another, and are “infected” by them even without noticing it. Beyond the fact that we assess people’s expressions and deduce their emotional states, there are cells in our brains called “mirror neurons,” which respond to other people’s actions by activating the same areas in our own brains, as if we were performing that same action.
But are we influenced only by the people we meet? It turns out that we are influenced by people we don’t even know. In the book, Connected: The Surprising Power of Our Social Networks and How They Shape Our Lives—How Your Friends' Friends' Friends Affect Everything You Feel, Think, and Do, Dr. Nicholas A. Christakis and Prof. James Fowler introduce the concept that every human being is meshed in social interconnections and networks. According to Christakis and Fowler, important aspects in our lives are influenced by people up to three degrees of remoteness from us, even if we don’t know them personally.
“Our own research has shown that the spread of influence in social networks obeys what we call the Three Degrees of Influence Rule. Everything we do or say tends to ripple through our network, having an impact on our friends (one degree), our friends’ friends (two degrees), and even our friends’ friends’ friends (three degrees). ...Likewise, we are influenced by friends within three degrees.” [89] Our health, wealth, and indeed happiness are largely a function of what people three degrees of remoteness from us think and do.