Ponzo Optical Illusion

The Ponzo illusion is an optical illusion that was first demonstrated by the Italian psychologist Mario Ponzo (1882-1960) in 1913. He suggested that the human mind judges an object's size based on its background.

The typical example of this is the figure below. This is the typical railroad track scheme usually used to represent this illusion. The vertical lines appear to go off into the distance like train tracks. This gives us the impression that the line in the distance is larger then the line that appears to be nearer to the viewer.


Seeing this illusion against a great real photo backdrop can be amazing. Most of the time people pick train tracks. Below is an outstanding photo that presents this optical illusion slightly different...

The two red lines below are duplicates, they are the exact same size. Which image is more convincing the one with two lines or the one with four lines?


-opticalillusions4kids