Our mind insists that this is an image of a cube, despite it being just 12 lines on a flat 2_Dimensional surface.
There are several interpretations: Is the dot in the centre or corner of a face? Is the dot at the front or the back?
Aside from these four options there is a fifth: That this is a flat image (the reality).
Although this is a completely static image, ones mind flips between different hypotheses for what it represents.
Where is the little circle? Front or back? Centre or corner?
The Necker Cube
This is an excellent web page that explores many aspects of the Necker Cube
It is incredibly difficult to view this Two-Dimensional image as anything other than a 3D object