W.g. Sebald said this quote

...and Věra said that every time we reached the page which described the snow falling through the branches of the trees, soon to shroud the entire forest floor, I would look up at her and ask: But if it's all white, how do the squirrels know where they've buried their hoard?... Those were your very words, the question which constantly troubled you. How indeed do the squirrels know, what do we know ourselves, how do we remember, and what it is we find in the end?