Your "2001: A Space Odyssey" reference made me smile, I like it. And that is our cage. That little "can't" ... Speaking in psychological sense (nothing to do with physics) we know that we "do not know" but, we do not know how to look for that unknown or usually we are very bad at it. Most of the time way how we look for the things can be compared with brutal force method in computing. Psychologically if we say that something is impossible, we are shutting down our brains to look for solutions, we are saying this is it, this is all we can ever hope for. Every time we say it is "impossible", "it will never work", "there is no point" those cage bars become a bit bigger and stronger. Do not get me wrong, I just like more when people intelligently try and failed thousand times trying to do something new, than when they give up at the beginning or just hold dearly to one standard already known thing. I'm afraid I can't do that, Dave. This is in the realm of known physics.