That a wall has always been red Does not mean it's not a white wall Painted red.
There is a mirror in you, That shows the space between the red and the white.
You can stand there, and observe how the red fibers' attached to the white wall.
If what you see is still red, Then you know the painter was there Before the mirror's light--yet even this action of the painter is also shown in the mirror.
If the painting is just one layered, Then everyone knows it's red paint. What fun for the spectator of this game?