A building whose position is totally unknown would be placed in
   the largest voxel; this being the root node that represents the
   entire world. Image Understanding in Unstructured Environment By
   Su-shing Chen, 1988 This is meaningful to me.* Let's take this
   out of its original context. a) you have the Universe. b)
   There's a thing. Ok. 1) What is that thing?* Who knows WHAT it
   is?* It's a thing. 2) Where is that thing?* Who knows WHERE it
   is, just that it belongs with the Universe. 3) When is that
   thing?* Who knows WHEN it is, just that it belongs with
   Universe. 4) Why does that thing belong to the Universe?*
   Because we said it did. 5) Who said that thing belongs with the
   Universe? Now THAT'S something we can answer