Negative space drawing, Willson, Orange, Hull, Art

A.  Negative space is space that no object is occupying.  You can clearly see negative space if you put an object against a piece of paper.  Everywhere you see the paper is negative space.
B.  I saw negative space in the cutout because it alternates between surfaces.  The first piece of paper is negative, then positive, then negative, and so on.  In my stool drawing I just drew the parts of the orange paper that I could see. 
C.  It helps an artist to see in negative space because it adds an entire new vantage point from which to create a drawing.
D.  Seeing in negative space can enhance a drawing because someone could be awful at regular drawing, and then be awesome at negative space.