Recent Scientific American blog post is a good, short, not-very-technical summary of why it’s important to think about human sociality — online and face-to-face — in terms of networks:
Modern research in sociology, psychology, neuroscience, and anthropology is showing that our world does not revolve around ourselves as individuals—contrary to Enlightenment and later claims that we are inherently self-centered creatures. Instead, what we are like as individuals critically depends on how we are linked socially and emotionally with others in relational networks reaching far and wide.
Why? We have evolved as a species to be quintessentially social creatures. Many plausible explanations have been proposed for why we are so. The bottom line, however, is a telling one. As the psychologists Lane Beckes and Jim Coan have observed, being a social animal gives us real advantages in the struggle for existence—a social baseline of emotional support and security. So much so, that perhaps far more than most of us realize, our human connections with others are in effect an extension of the way our brain interacts with the world.