Well, that all depends on how you look at it …
Ambiguous image illusions seem to simultaneously point out limitations in our visual system (dependence on shapes, edges and previous experiences in interpreting what’s in our visual field) as well as its flexibility (because in the end, most of us can see both shapes).
Think about that while you explore the young lady/old lady, rabbit/duck and whale/kangaroo illusions above.
I wonder how these work for people who experience “face blindness”, the inability to recognize and identify faces. Radiolab explored that condition previously.