A "proof"

This animation shows how Da Vinci used the Mirrored effect in his art. You'll see two female faces that are in the same drawing. Both faces that are opposite from each other, are actually exactly the same. This couldn't be realized or shown without being mirrored.

Da Vinci wrote mirrored, meaning that you have to look in a mirror to see his writing from left to right. He wrote from right to left. These two faces are exact mirrored opposites. The face to the right is the EXACT same to the left. When they are mirrored - turned from left to right, as seen in a mirror, they align exactly. See for yourself. This is proof that Da Vinci implimented this phenomena in his art, which is one of the "theories" I describe in my book. There is another clue in this drawing that alludes to this being Da Vinci's intent. Which i'll describe and demonstrate later, or maybe you'll have to buy the book!