"each hour of the day brought me a different memory. Morning, when the sky was a hard, light blue, I thought of beaches on the Atlantic: at noon I saw the sun and I remembered a bar in Seville where I drank manzanilla and ate olives and anchovies: afternoons I was in the shade and I thought of the deep shadow which spreads over half a bull-ring leaving the other half shimmering in sunlight: it was really hard to see the whole world reflected in the sky like that. But now I could watch the sky as much as I pleased, it no longer evoked anything in me."
(Jean-Paul Sartre, The Wall)

"You have shown me a strange image, and they are strange prisoners. Like ourselves... and they see only their own shadows, or the shadows of one another, which the fire throws on the opposite wall of the cave"
(Plato, Republic)