This is Nabokov’s note to Alfred Appel, Jr. (the annotator) on symbols and colours:
“There exist novelists and poets, and ecclesiastic writers, who deliberately use color terms, or numbers, in a strictly symbolic sense. The type of writer I am, half-painter, half-naturalist, finds the use of symbols hateful because it substitutes a dead general idea for a live specific impression. I am therefore puzzled and distressed by the significance you lend to the general idea of “red” in my book. When the intellect limits itself to the general notion, or primitive notion, of a certain color it deprives the senses of its shades. In different languages different colors were used in a general sense before shades were distinguished. (In French, for example, the “redness” of hair is now expressed by “roux” meaning rufous, or russet, or fulvous with a reddish cast). For me the shades, or rather colors, of, say, a fox, a ruby, a carrot, a pink rose, a dark cherry, a flushed cheek, are as different as blue is from green or the royal purple of blood (Fr. “pourpre”) from the English sense of violet things, to discriminate between visual shades as the author does, and not to lump them under such arbitrary labels as “red” (using it, moreover, as a sexual symbol, though actually the dominant shades in males are mauve—to bright blue, in certain monkeys)…. Roses may be white, and even black-red. Only cartoonists, having three colors as their disposal, use red for hair, cheek and blood.”
2/ That reminds me of a passage in his Lectures on Russian Literature:
“The difference between human vision and the image perceived by the faceted eye of an insect may be compared with the difference between a half-tone block made with the very finest screen and the corresponding picture as represented by the very coarse screening used in common newspaper pictorial reproduction. The same comparison holds good between the way Gogol saw things and the way average readers and average writers see things. Before his and Pushkin's advent Russian literature was purblind. What form it perceived was an outline directed by reason: it did not see color for itself but merely used the hackneyed combinations of blind noun and dog-like adjective that Europe had inherited from the ancients. The sky was blue, the dawn red, the foliage green, the eyes of beauty black, the clouds grey, and so on. It was Gogol (and after him Lermontov and Tolstoy) who first saw yellow and violet at all. That the sky could be pale green at sunrise, or the snow a rich blue on a cloudless day, would have sounded like heretical nonsense to your so-called "classical" writer, accustomed as he was to the rigid conventional color-schemes of the Eighteenth Century French school of literature. Thus the development of the art of description throughout the centuries may be profitably treated in terms of vision, the faceted eye becoming a unified and prodigiously complex organ and the dead dim "accepted colors" (in the sense of "idees recues") yielding gradually their subtle shades and allowing new wonders of application. I doubt whether any writer, and certainly not in Russia, had ever noticed before, to give the most striking instance, the moving pattern of light and shade on the ground under trees or the tricks of color played by sunlight with leaves. The following description of Plyushkin's garden in Dead Souls shocked Russian readers in much the same way as Manet did the bewhiskered philistines of his day...”Nabokov teaches you how to see things, but it’s not only about colours—he teaches you to really see things, to get rid of clichés and general notions, to see nuances and shades and the individual instead of thinking in general terms and categories.