1/28/2004   slide 10
Rule 2: Connections Stay Connected
•“If the tips of two lines coincide in an image, then always interpret them as coinciding in 3D.” [Hoffman 1998 p27]
Illusion Works page
Hoffman p 27
Escher, Maurits Cornelis
Belvedere
1958
Lithograph
46.2 x 29.5 cm (18 1/4 x 11 5/8 in.)
Rules 1 and 2 work only for generic views. If you’re at a weird view where things line up strangely, you may get shape wrong. But even when discover truth, you cannot change how you see it (!)
Rules enable us to see, but also blind us to countless possibilities we can never see because our rules forbid it.

http://www.artchive.com/artchive/E/escher/escher_belvedere.jpg.html