V.V. sought to express something, which until expressed had only a twilight being (or even none at all--nothing but the illusion of the backward shadow of its imminent expression). It was Ada's castle of cards. It was the standing of a metaphor on its head not for the sake of the trick's difficulty, but in order to perceive an ascending waterful or a sunrise in reverse: a triumph, in a sense, over the ardis of time.

Author: Vladimir Nabokov