I am part way through watching Back to the Future2 and already some discrepencies spring to mind.
As mentioned earlier, Dr Brown travels from 2015 to 1985 in order to collect Marty and help change his destiny by using young Marty to impersonate his son in the future and prevent a robbery taking place, which initially throws Marty's destiny into disarray.
The problem here is that by removing Marty from 1985 and rematerialising in 2015, this should create a future where Marty has been missing for 30 yrs, the future that Doc and Marty arrive in should be a parelleled version where no Mcfly family exist. Unless of course using perception 3, it is assumed that Marty eventually makes it back to 1985 in order to concieve his child, which he infact does (by the end of the series), which actually restores order of timelines and makes the writers much more intelligent and aware of the full temporal implications of the storyboard,
Incidentally, why doesnt Doc Brown just travel to 1985 and TELL Marty the future mishap, such information could be used 30 yrs down the line to prevent his son taking part in the robbery.
Incidentally, do you remember in the first film when Marty's hand started to dissapear because he failed to exist anymore? Well this is seen again as old 2015 Biff Tannen, returns to 2015 after stealing the Delorean Time machine and sucessfully handing the sports book to young 1955 Biff. Here we see poor old Biff is being undone from the new time lines, continuity praised. However, surely the broken walking stick that he leaves inside the car would also have vanished? If that happened, it would make sense to me.
and of course puts me to shame at the same time.
This has the same effect but is much simpler than using a young 1985 Marty to participate in a covert impersonation of his future son.
This diagram shows how the timelines have skewed into creating both an alternate 2015, as a result of the Marty and Doc future-Robbery-interaction, and also an alternative 1955 timeline as a result of the old 2015 Biff Tannen taking the sports book back to his younger self in 1955.
Although the diagram supports both parellels taking place, and so upholds the films storyboard, who is to say that the journey that Marty and Doc take back to 1985 should place them into the alternate 1985, just because of the 1955 alt taking place?
Since, via perception 2, the shabby 2015 where the Mcfly family are laid to jail exists in a parellel with the new improved alt 2015, where everything is fine, then also the original 1985 together with the Biff Tannen alt 1985 must also co-exist. Yet it is presumed that the alt1985 (which was created as a reult of the alt1955) is the destination of our heroes journey back from the future.
When Marty travels back to 1985 Alt, he visits his mother who, due to the Tannen alternate 1955 scenario, now lives in a high-rise Casino with Multi-millionaire Biff Tannen.
Biff looks at young Marty and screams " you're meant to be in Switzeland " which suggests that after the 1955 skew, lorraine and George McFly still manage to conceive baby Marty, and that an alt1985 Marty still resides.
This holds well with perception 2. The parellel can still allow similar events taking place, and certainly allows multiple versions of yourself floating around within a singular timeline.
The confusion only arises when the film-writers confuse perceptions and allow individuals to be removed from one timeline and pocket back into the same timeline with multiple selves, as in the original 2015 journey.
Unless of course the delorean time machine is not only capable of selecting a time destination but also a parallel reality destination as well.
Towards the end of Back to the Future2, as Marty and Doc manage to repair timelines, the newspaper headlines which they obtained from alt1985 change before their very eyes. this suggests that future is changing. However evidence from the future which alters due to past interaction does not fit into any of my 3 perceptions of timeline causality.
Perhaps it is me at fault, and I have to invent a fourth perception. However, perceptions as they are, if a future newspaper headline has changed then this implies that the original headline should also have changed. In which case, why would Marty tear out and keep in possession a newspaper headline which honours his father instead of reports his murder, and why should Doc Brown decide to remove a headline which comends him instead of committing him? although these newspaper headline alterations confirm and celebrate the pairs successful mission, they are infact small paradoxes.
Despite the newspaper changes, after one hour into Back to the Future2 the film decides to follow Timeline perception 3 perfectly, where past interaction was a part of the usual history timeline anyway. Proof of this is seen as the BTTF2 marty interacts with the occurences of the BTTF1 Marty in 1955 without causing paradox or effecting the original films storyboard. The final 40 mins of Back to the Future2 present itself as a scientific joy to watch, as it completely follows the third perception of time causality. That is with the newspaper headline as an exception.
In conclusion.
I understand that I have been harsh whilst reviewing Back to the Future and its sequel, but I am quite capable of sitting back and just enjoying the film for what it is, fantasy entertainment.
It just amuses me to nitpick at the time implications along the way.
I am interested in continuing this analysis on Back to the Future3, however
I seem to remember the final segment of the trilogy being somewhat too romantic
and scientifically boring.
I may decide to add a further page to my BTTF webpage disections.
We shall see, in time.