A paradox, in time travel, is “a situation in which the effect of an incident contradicts or eliminates the cause of that same incident”.
The classic example of this is the “Grandfather paradox”. An example of this would be in which a person travels back in time and kills his/her grandfather before the latter met the time traveller’s grandmother. This results in the erasing of his/her own existence — and raises the question, if he/she never existed, how could he/she travel back in time to kill his/her grandfather?
According to Dr. Emmett Brown, a paradox could ultimately unravel the very fabric of the space-time continuum and destroy the entire universe (or at least the Milky Way galaxy) and had to be avoided.
Whilst the Back to the Future films are among the cleverest and most enjoyable films I have ever watched.
They are still not completely devoid of any errors. I’ve decided to list some of the paradoxes and plot holes in the Back to the Future trilogy. I hope you have fun reading.
1. George and Lorraine would recognise their son
One of the things that I questioned, quite possibly on my first viewing of the original film, was that George and Lorraine didn’t notice that their son was the person that helped them get together back in 1955. You’d almost certainly remember the person who played Johnny B Goode in such dramatic fashion at the Enchantment Under The Sea dance. Lorraine even had such a crush on Marty so it would be unlikely that she’d forgotten him altogether, even after 30 years. Wouldn’t, when Marty gets to the age of 13 or 14, one of them think that something a bit strange was happening?
2. The Doc Would Know He’s Going To Die
At the beginning of BTTF 3, Marty who’s currently in 1955, learns that Doc Brown has been transported back to 1885 and had been shot and killed that same year by Bulford “Mad Dog” Tannen. Marty immediately contacts the younger version of Doc Brown living in 1955 to request his help going back to 1885 to save Docs older counterpart. Since the younger Doc then learns of his own fate, shouldn’t this mean that the older version of Doc Brown would instantly know what was going to happen too? Hence, if he had any sense, the Doc would, at the very least, pay Buford Tannen the $80, and avoid getting shot.
3. Why does Jennifer look shocked when she meets herself?
In a similar vein, there’s a point in Back To The Future Part II when the older Jennifer meets younger Jennifer in 2015. Yet, surely older Jennifer would know that younger Jennifer was going to be in the house as she’d definitely remember a momentous event like this happening 30 years previously.
4. Couldn’t the Doc make gasoline?
In 1885, the big problem Marty and the Doc face is that they can’t get hold of gasoline to power the Delorian. At this stage, the Doc has the knowledge and expertise to build a time machine, not to mention many other complex inventions. Why wouldn’t he be able to get hold of some kerosene (which was available in 1885) and make some gasoline by refining it?
5. Would Marty and Jennifer and their children exist in 2015?
At the point that Marty and Jennifer step into the Delorean at the end of the first film and head off to 2015 to do something about their kids, how can there still be kids there to find? If you think back to the first film, Einstein gets sent one minute into the future. For that minute he doesn’t exist in 1985, until he returns. Thus, the rule is established there, and if it’s followed, then the McFly family would not exist in 2015. As far as the strict laws of the timelines go, if Marty and Jennifer disappear, even temporarily from 1985, then events in the future would change until they return. As such, the future Marty and Jennifer shouldn’t be there, and nor should their kids.
6. The Doc couldn’t have invented the time machine?
In Back To The Future Part II, when Marty and Doc have travelled back to the alternative 1985, we learn that the Doc has been committed several years before. This presents a problem. At the point in 2015, when old Biff takes the Delorean and gives the Almanac to young Biff, then surely the time machine should cease to exist, leaving Marty and Doc stranded in 2015 and old Biff stranded in 1955?