[Chyron8472]

Originally Posted by FaMzNeSS

Actually, I remember why I thought this would ring true in Back to the Future Logic. It's the same logic that when Doc, Marty and Jennifer travel to the future, Marty and Jennifer still exist in an uninterrupted timeline.

Basically, there was no surefire way they would have returned back to 1985 to continue on with their "normal" lives, however... they still existed in the future. In theory, since they departed from 1985 and hadn't returned yet their future selves wouldn't exist because they hadn't yet returned to 1985 to restore the timeline.

I don't understand what you're saying here.

Also, I know that the BTTF DVD FAQ posits that time traveling into the future takes you to a future based precisely on events only leading up to the point that you left. I really don't like this idea because it suggests that every variable choice made by everything and everyone everywhere in the universe during the intervening years can be easily calculated based on past events without any statistical error. I also don't like for an FAQ on a DVD to be considered as irrefutable fact and the basis for all things explainable in BTTF science. As I recall the FAQ itself even says something to the effect that the answers it gives are only some possible explanations posited and not to be considered as absolute truth.

Anyway, regarding the future-of-the-exact-point-that-you-left idea. I posted my thoughts on this earlier in the thread:

Originally Posted by Chyron8472

That would mean that the time-continuum makes a lot of assumptions about various future events along the way. Throughout time a lot of seemingly minor events can coalesce together to create a major turn of events. In Jurassic Park, Ian Malcolm says "A butterfly can flap its wings in Peking and in Central Park you get rain instead of sunshine." When you change one thing, it has the capacity to change something else, which can change something else... there are a lot of assumptions to make about "the most likely outcome of events" and as the time-continuum itself is neither sentient nor capable of computing probability algorithms, I don't understand how it could be able to intelligently assume which choices over time would be the more likely to occur.

It sounds like you're saying that the time-continuum is capable of playing a highly elaborate guessing game. If this were true how does it assume that flying cars are practical to research and develop? How does it know which car companies would build which cars? If this were possible, would it then also be that if Doc had successfully finished the time-machine in 1955, if he travelled forward from then that the continuum's assumptions of the future he would see would be more like The Jetsons? What would the continuum assume the future would be like if someone travelled forward to 9999 A.D. using only probabilities known at 1985? How can the continuum possibly assume anything at all with so little information? The only reasonable answer at the very least pushes BTTF's interpretation of the future into the realm of intelligent design theory, which is another way of saying that Doc went forward to 2015 to witness God's Will for the universe before it actually happens. I never thought of the BTTF movies as touching on matters of spirituality, so it doesn't really fit.

Plus, how does the continuum itself decide what the "present" is? When Doc goes to 2015, since he is the first to visit it, his present at that time becomes 2015 and going back to 1985 then changes the past as he then knows it. It would be the same as if Doc had been cryogenically frozen for 30 years, reanimated and then time-travelled back to 1985. Doc travelling forward in time from 1985 to 2015 for the first time forces the continuum to lay out events, such that when Doc reaches 2015 they no longer will happen but already have happened.

To say that Doc can visit a future that doesn't really exist yet, or merely a "projected destiny" as you put it, is to say that the time-continuum only becomes set as quickly as it takes for the fourth-dimension to march forward in time; that at the time of BTTF, whatever exists before 1985 is set and events that come afterward are only "projected" or "assumed" by the continuum even when someone goes into the future and gains significant amounts of experiences there; and that the continuum itself is capable of making intelligent choices however extraordinarily large or infinitesimally small, and is able to do so many millenia far into the future of what is considered the present, with incredibly little data to base such projections on.

Originally Posted by Chyron8472

I never said BTTF should follow the mechanics of predestination. What I'm saying is that the future isn't written yet unless someone already knows what it is. When someone time-travels into the future for the first time, they essentially are removed from the fourth dimension until the continuum catches up to where their destination is. When they arrive, that future then can be considered their present. Then, if they return to the previous time they came from, variations in the timeline that occur as a result of their actions overwrite the events that were recorded on the timeline previously.

Einstein at the beginning of BTTF1 skipped forward in time and when he reappeared no second Einstein was there. Also, when Doc went to 2015 at the end of BTTF1, I believe he also appeared in a 2015 where no other Doc was there because the time-continuum recorded events that occurred in his absence. Those recorded events remained until events in that 2015's past were altered. So when Marty, Doc and Jennifer went to 2015, it was the 2015 that had no other Doc. If Marty and Doc had gone together to 2015 first, the future would have been laid out without either of them just as it was laid out for one minute with no Einstein at the beginning of BTTF1.

I understand that the message Doc gives at the end of BTTF3 is "the future is whatever you make it" and "your future hasn't been written yet, no one's has," but just because Doc says these things to Marty to encourage him, it doesn't mean that the time-continuum has to agree.

And I know you really really want the Marty at the end of BTTF3 to be the one original Marty0, but it just doesn't make sense for him to be. By the nature of being able to witness his own future first-hand, it means he can't be the first ever Marty since he never makes that choice. He essentially is learning from a mistake someone else already made... and that someone else is himself, only a previous version that has already made the choice.

So basically, my thoughts are that when Doc goes to the future by himself, he finds a future in which Marty and Jen are there but Doc's other self is not. When he goes back in time, he is altering the past by taking Marty and Jen, so the Marty and Jen seen from the point that Doc shows up at the BTTF1's end/BTTF2's start are not the original versions of themselves.