From The art of looking sideways, by Alan Fletcher.

I shut my eyes in order to see. – Paul Gauguin

It is only with the heart that one can see rightly. What is essential is invisible to the eye. – Antoine de Saint-Exupery

I paint what I know, not what I see. – Pablo Picasso

What you see is what you see. – Frank Stella

Seeing is not believing. Believing is seeing. – Robert Pirsig