The psychological effects of losing all but our closest ties can be profound. Peripheral connections tether us to the world at large; without them, people sink into the compounding sameness of closed networks. Regular interaction with people outside our inner circle “just makes us feel more like part of a community, or part of something bigger,” Gillian Sandstrom, a social psychologist at the University of Essex, told me. People on the peripheries of our lives introduce us to new ideas, new information, new opportunities, and other new people. If variety is the spice of life, these relationships are the conduit for it.
The physical ramifications of isolation are also well documented. Julianne Holt-Lunstad, a psychologist and neuroscientist at Brigham Young University, has found that social isolation increases the risk of premature death from any cause by almost 30 percent.