INVISIBLE CITIES -- Opposites (and an announcement)

I am reading Invisible Cities, by Italo Calvino, very slowly.  And intentionally so: it is meant and it demands to be savored.  If you read anything here at The Wall, be advised, this is our next book, once we're done with Kipling's Kim; you may want to secure a copy.  (And unlike Kim, I will have read this before its public blog-reading, and since I already know that it's absolutely brilliant, there will be none of this eggshell-walking, fingernail-biting over the book's worth.)  While reading a couple cities' worth sitting out my son's Karate class today, I was struck--just shy of literally, actually--by (well, simultaneously) this passage (it does, unfortunately, pale somewhat out of context):

A sibyl, questioned about Marozia’s fate, said, “I see two cities: one of the rat, one of the swallow.”

…

I have come back to Marozia after many years: for some time the sibyl’s prophecy is considered to have come true; the old century is dead and buried, the new is at its climax.  The city has surely changed, and perhaps for the better.  But the wings I have seen moving about are those of suspicious umbrellas under which heavy eyelids are lowered; there are people who believe they are flying, but it is already an achievement if they can get off the ground flapping their batlike overcoats.

The way the book comes together, as well as the overall construction of this particular city, renders the rat and the sparrow opposites, yet, simultaneously, twins--a yin and yang.  Out of context, does the comparison still work?  The question, "What is the opposite of rat?" is groaningly alike to those old, irritating (though, admittedly, often quite funny) Netflix quiz-show radio ads--you know, "Was Abraham Lincoln too honest?"  But look at it: yeah, a pretty direct comparison works.  A sparrow really is pretty much the parallel opposite of the rat.


Thoughts?

bonus simile from the same city: something evanescent, "as transparent as a dragonfly."