I will rewrite it into a story; its flexibility shows what I am
   referring to:

   "Nobody could figure out Mr. Difference. Whenever the children
   looked at Difference, their brains went blank, their eyes saw
   something but their brains could not make heads-of-tails of Mr.
   Difference. What or Who is Mr. Difference? There was no way to
   know. Adults couldn't see him at all.

   But I'm friend with Mr. Difference. He has explained himself to
   me somewhat.

   "Where do you live, Mr. Difference", I asked him.

   He replied, "I live inbetween".

   "What do you live inbetween?" I replied.

   "I live inbetween two unique things, even if they're not
   things." he answered cryptically.

   Confused, I asked, "What do mean by "things"?"

   "Singularities, my boy. Singularities."

   He points to two houses in the distance. They have signs on top.
   Singularity 1 and Singularity 2.

   "But how can you live there, " I replied. "There's no house
   inbetween those houses!"

   "Precisely!" he answered, as he disappeared in a puff of
   nothing. In fact, I don't know if he was ever even there at all.

   [based on this]
   Mind you 'difference-in-itself' cannot be thought. Difference is
   between at least two posited things (singularities).
   I wrote a long time ago a point relevant to this: 'You can see
   how two things differ, but you cannot see the difference' -
   Difference is not something that is seen, it is that by which
   lacks between singularities. Difference is incorporeal.