Let's imagine for a moment that reincarnation is true (and, no, all of those concerned for my orthodoxy, please don't send me the scripture references proving that it's not. This is a thought experiment. A fantasy, OK?) Now assume something else: that when your soul departs for the great waiting room in the sky where you hang about until you get your next posting, you are beyond space and time. That is, the waiting room doesn't follow our linear timescale and it is quite possible for your next life to be historically before the one you have just exited from. Or, it might be that you are reincarnated contemporaneously with your current existence. With me so far? Now let's say, purely as a fantasy that the second scenario holds: that you come back again, in a different body and live a different life, but you live it at the same time as your current life. You could run into yourself in the street, and of course you would never know it. Now lets take an even greater an...