The reason you can never find your cat when you are looking for her. (i use her because my cat is female and it is easier to type than he/she. Forgive me, those who own male cats.) Cat-space is an alternate dimension into which cats vanish without warning. No amount of looking, begging, or pleading will call her back from her inter-dimensional hidey-hole, although sometimes a can of tuna will do the trick. If you ever noticed your cat vanish, you look in all her favorite spots, call for her, anything... and then she waltzes out from the first place you looked, several hours later, she has been in cat-space. If you see a cat vanishing under a chair or a bed and then look there moments later, she has entered cat-space. Just *try* to find her... you won't, not till she chooses to come back