We should always keep an open mind about any new phenomenon in nature. To merely say that's impossible, therefore it doesn't exist, is to commit a serious error. A much better approach would be to say That's quite unlikely, but show me the evidence you have that says that it may be so. It would be the height of arrogance to think that man knows everything possible about the Universe or the Earth. There are many things yet to be discovered, and that is why we have scientific research (or any kind of research). That should be the rationalist's approach to parapsychology and the occult.