[quote][b]Posted by:[/b] Liu Xuande What makes peope think that time is preserved in a way we can 'go back' to it anyway? In the first episode. I've always thought, that when marty sees himself using the car to escape from libyans the marty in the car should be able to see himself on the banking. This would in turn mean that we have no control over our lives and that everything just plays out. Not to mention any time travel into the past would inevitably cause an endless loop. If say you went back and saw yourself, you would endlessly do the same thing. This shows that the future exists now, and is shaped as the present world changes. (yes I love BTTF, Great Film)[/quote] i think we are only thinking about "instant" forward time travel via wormholes here. free will has always been a problem with time machine theories though. actually i think einstein realised the potential his theories had on free will and said some nice things to cover himself up... can't think of any off the top of my head. traditionally people don't like free will, but from a causality standpoint it doesn't really exist at all(unless you believe there is something on a quantum level affecting our decisions, which is unlikely).