Grades 3–5 · Organisms
How can one picture look like a vase or two faces?
A picture can have an outline that fits more than one object. In the vase-and-faces picture, the same curved boundary can outline a central vase or the profiles of two people looking toward one another.
In the diagramOne boundary can support two interpretationsvaseface →← faceThe center and sides share their outlines; the drawing does not change.
Your eyes receive light from the drawing, but seeing involves more than recording that light. Your visual system organizes regions into objects and background. Giving the center the role of object makes the vase easier to recognize.
Giving the side regions that role makes the faces easier to recognize. The printed boundary has not moved. What changes is how the pattern is organized in your perception, and your experience may shift between the interpretations.
This does not mean your eyes are broken or that every picture is equally uncertain. Usually many clues agree about the objects around us. An ambiguous drawing deliberately leaves clues that support more than one arrangement.
About this explanation
Starting knowledge: Distinguish the outline of an object from its background and recognize a face in profile.
Sources
- American Museum of Natural History — Optical Illusions: Selecting