My two cats are seeing something I cannot see... They keep looking up at the ceiling and up walls, and they hold their gaze at whatever they are viewing. It's not flying bugs either. My only rational explanation is they might hear something on the roof or possibly in the attic such as squirrels or birds, but I live in an apt and I cannot hear anything. I do NOT believe in ghosts, and it's heretical to believe in such nonsense, therefore, I certainly rule that out; but could cats possibly see or detect angels or, God forbid, evil spirits present in a house?