if everything is invisible, how come we can still see the cat, the door, the walls, the...photo? a photo of invisible everything should be empty. however, that would also make it a picture of nothing. yet, nothing, by virtue of being even merely a concept, becomes something--that is, nothingness is self-negating. if everything in that photo were invisible, it would be identical to a picture of nothing, hence it would be something (even as an image of noting), and the "invisible everything" would also be negated.