At the heart of much speculative fiction (and fiction in general) is a question. What if? On Tuesdays I like to throw one out there and see what you make of it. Do with it as you please. If a for-instance is not specified, feel free to interpret that instance as you wish. And if you find this becomes a novel-length answer, I'd appreciate a thank you in the acknowledgements.
What if our lives are actually just a training period for something else?