A visual representation is not a kind of illusion where our attention slips back and forth from seeing lines and colors to seeing the scene represented, it is not like we switch from giving in to the illusion to noticing it, like in the duck, rabbit illusion. We see a two dimensional canvas with lines and paint and IN this we see something three dimensional. It is not like we imagine the Princess Marguerite AS paint and canvas but we see her IN the paint and canvas. It is not about imagining or being fooled by illusion, it is a peculiar kind of seeing. When you see the duck rabbit you can see only one at the time, but when you see a painting you see the twofoldness at the same time. We get lost in the painting without forgetting that it is a painting.

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