This reminds me of the fable of the bear who couldn't sleep. This was back in the days of no air conditioning, mind you, so you have to keep that in the back of your head while I'm telling this story. Don't go getting ideas about bears having air conditioning units in their caves, cause it ain't happening. Not on my watch. Think about the practicality of it. Now, I'm not going to say bears are stupid animals, but do you really think one of those brutes could change an air filter? I doubt they would even know where to go to buy air filters. And even if they knew that, I bet they couldn't locate them in the store. But that would only be if there was a store that would allow a bear to come in and shop, and, to my knowledge, none of those exist. Then again, I've never lived in what you could call a "bear friendly community," so it could be that in different areas of the world, this is an acceptable practice. But that's beside the point, the point is, this particular bear did NOT have air conditioning in his cave, and due to his inability to regulate the temperature of his shelter, he found it very uncomfortable most of the time and had trouble sleeping.The moral of the story is: if you don't have air conditioning, or your air conditioning is not working, a ceiling-mounted fan is the next best thing.