The Figure/Ground Illusion

What do you see when you look at this image? Dildos? A butt plug? A chalice? Notice how your perception of the objects shifts back and forth. Can you see all of them at the same time?

How it works: This image is modeled after the famous Rubin vase, which depicts two silhouette faces in profile looking toward each other. The space in between them outlines a vase or urn in a contrasting tone. Depending on whether your perception is focusing on the dark area of the picture or the light area, you will see either the vase or the faces, but not both at the same time. Your brain has difficulty processing the two different interpretations of the contours simultaneously.