Seneca was right: “No one can live happily who has regard to himself alone and transforms everything into a question of his own utility.” John Donne was right: No man, woman, or child is an island. Aristophanes was right: We need others to complete us. We are an ultrasocial species, full of emotions finely tuned for loving, befriending, helping, sharing, and otherwise intertwining our lives with others. Attachments and relationships can bring us pain: As a character in Jean-Paul Sartre’s play No Exit said, “Hell is other people.”57 But so is heaven.