Illusion
I chose to work with the illusion of negative space. Negative space is a type of bistable perception, where it is possible for the viewer to see multiple images from the same shapes depending on how they interpret the artwork. Negative space artwork is one of the easier examples of bistable perception, since most instances are intentionally made quite obvious or are a matter of mentally selecting one or two main colors to view as the background, and all of the rest as the foreground objects in the image.