"Nostalgia, to me, is not the emotion that follows a longing for something you lost, or for something you never had to begin with, or that never really existed at all. It’s not even, not really, the feeling that arises when you realize that you missed out on a chance to see something, to know someone, to be a part of some adventure or enterprise or milieu that will never come again. Nostalgia, most truly and most meaningfully, is the emotional experience—always momentary, always fragile—of having what you lost or never had, of seeing what you missed seeing, of meeting the people you missed knowing, of sipping coffee in the storied cafés that are now hot-yoga studios. It’s the feeling that overcomes you when some minor vanished beauty of the world is momentarily restored, whether summoned by art or by the accidental enchantment of a painted advertisement for Sen-Sen, say, or Bromo-Seltzer, hidden for decades, then suddenly revealed on a brick wall when a neighboring building is torn down. In that moment, you are connected; you have placed a phone call directly into the past and heard an answering voice."
Michael Chabon at The New Yorker