To See and Not See

"Perceptual-cognitive processes, while physiological, are also personal -- it is not a world that one perceives or constructs but one’s own world -- and they lead to, are linked to, a perceptual self, with a will, an orientation, and a style of its own. This perceptual self may itself collapse with the collapse of perceptual systems, altering the orientation and the very identity of the individual." - Oliver Sacks, "To See and Not See", An Anthropologist on Mars, New York: Vintage, 1995