Paper? Now you see
it, now you see
it.
I see white paper. But this is a twofold seeing; there are two visions: sensous vision and categorical vision. The difficult lies in the double signification of seeing--a double signification that already governs Plato's philosophy. The difficulty consists in that if I see white paper, I do not see the substance in the same way "as" I see the white paper. Antisthenes already expressed this diffuiculty for Plato: "O Plato, I surely see the horse, but I do not see horsehood."
P. 66-67
Paperhood, the form for the categorical intuition of paperness.