'Sometimes when we meet another person we have an instinctive sense that we're going to get on well with them, that the possibilities of friendship are open. This is not only because we find that we can rub along comfortably with them, work amicably with them, find them interesting (although obviously these aspects are important); in that initial moment it's often the feeling that there is something about their mode of being, about the texture of their inner life, which seems unfamiliar. There are convivial friendships based on congruence of interest or taste. And there are, more rarely, friendships based on congruence of spirit. "You seem to know," the feeling goes, "what it is like to look out at the world from behind my eyes, and not because I have told you.'"
John Armstrong, Conditions of Love, p.52.