Whenever you suggest that history is a matter of losses as well as gains, whenever you call attention to what we’ve lost along the way, whether it’s something we deliberately set aside or something we just forgot to pack, a great chorus starts shouting “Nostalgia!” You may not even want to have packed it; you may think that we chose as well as we could have in the circumstances; but you need only hint that something of value, even of some tiny tiny value, that we once held we hold no longer, and it starts: “always the loud angry crowd, / Very angry and very loud,” crying: “Nostalgia!”

It’s a bullying cry, but they’re not bullying you, at least not primarily. They’re bullying that little voice within them that wonders whether there might be more to the future than “everyone young going down the long slide / To happiness, endlessly.” Nothing could be more essential than to silence that quiet, that ever-so-gently skeptical voice.