36

The night on the first part at the Two Pine mall and when all the ruckus happened, Doc Brown already programmed the time machine to go to Nov 05 1955.

Why so? I mean, I don't recall if there is a reason for that or it was only chance or no reason at all. If this was the first time tested, perhaps he could have gone to the Old West, or wherever.

But why, in-universe, did he choose that time? Does it have to do with the flux capacitor?

8
  • 9
    Not really a duplicate, because that question had to do with specifically the Out of Universe reasons, while this is specifically the In-Universe reasons. Commented Sep 2, 2019 at 21:57
  • 10
    Keep in mind that he was just demonstrating the device to Marty, he wasn't intending to actually travel to any of the times he programmed in. (I mean, he might well do so later, but probably not for the first trip.) Commented Sep 3, 2019 at 0:18
  • 1
    @riccs_0x, when Doc was typing date he wasn't even demonstrating time machine, but just interface for entering dates. So he was just typing semi-random dates. For first actual time travel he was planning to go to the future, and he did so in the end of the movie.
    – user28434
    Commented Sep 3, 2019 at 9:20
  • 5
    VTO; not a duplicate since this one requests (and receives) in-universe answers, where the other one asked for (and received) an out of universe answer. Commented Sep 3, 2019 at 18:33
  • 5
    Of course Valorum thinks it's a dupe, it's his answer in the other question. Pretty par for the course there. Re: the meta post... there doesn't seem to be a consensus there, so not sure what the point is. You say "semi-dupe", I say it's a completely different question that got different (and complete) answers. Commented Sep 3, 2019 at 19:16

4 Answers 4

108

The date was already personal and memorable to Doc, because it was the date he invented time travel:

Doc: Say, you wanna see the signing of the declaration of independence, or witness the birth of Christ. Here's a red-letter date in the history of science, November 5, 1955. Yes, of course, November 5, 1955.

Marty: What, I don't get what happened.

Doc: That was the day I invented time travel. I remember it vividly. I was standing on the edge of my toilet hanging a clock, the porcelain was wet, I slipped, hit my head on the edge of the sink. And when I came to I had a revelation, a picture, a picture in my head, a picture of this. This is what makes time travel possible. The flux capacitor.

It later became a plot point as Marty uses that story to track down Doc and convince him he's from the future, because he just had the idea and Marty could explain exactly how.

7
  • 3
    But - Doc says "here's a red letter day in science" and then he never finishes the thought. It's as though something else important happened on the same day, and when going to say what that event was, he remembered that was also the day he invented time travel - so, from a certain point of view, we still don't know why he initially chose the date
    – NKCampbell
    Commented Sep 3, 2019 at 18:53
  • 10
    @NKCampbell: As the time machine derived from the thought he had that memorable day is standing right beside him, and had just made its maiden voyage successfully, it is pretty clear to me that "the breakthrough thought that led to time travel being possible" is exactly what Doc is referring to as "red-letter date in the history of science".
    – DevSolar
    Commented Sep 4, 2019 at 6:10
  • 2
    It's part of the standard proof against the possibility of time travel. You make a statement on a day you'll remember: "If I ever invent time travel, my first act should be to come back and visit myself on this day to tell me I've done it." If you don't then see your future self on that day, you can prove that you will not invent time travel. (You can then extend this to anyone else inventing it by making a public statement that will be recorded for all of history instead.) Commented Sep 4, 2019 at 14:53
  • 2
    @DarrelHoffman Or, you invent time travel and just don't go back in time to tell you you've done it.
    – wizzwizz4
    Commented Sep 4, 2019 at 18:10
  • 2
    @Miral The Doc that utters the line about the "red-letter date" does not remember meeting Marty, but he does remember the date as the one he hit his head and had the idea that made the DeLorean standing right beside him possible.
    – DevSolar
    Commented Sep 5, 2019 at 9:35
37

Doc wasn't intending to go to November 5, 1955 with his first trip. His desire was actually to go to the future:

Marty: The future, it's where you're going?

Doc: That's right, twenty five years into the future. I've always dreamed on seeing the future, looking beyond my years, seeing the progress of mankind. I'll also be able to see who wins the next twenty-five world series.

In the movie, Doc was demonstrating to Marty how the time machine worked. He showed Marty how to program the time machine and used three example dates of important moments in history, showing Marty how to enter them into the machine. The November 5, 1955 date was simply the last of the three examples that was entered.

After Doc got into the machine for his first trip, he could have entered any date he desired before leaving. Unfortunately, as we all know, his plans were interrupted by the Libyans, and Marty accidentally traveled to the last date that was entered into the machine.

1
  • 7
    This: he punched in each date, one at a time, to demonstrate the functionality. It would seem that, for the last date, he could remember that the date was significant, but he didn't remember why it was significant until after he'd punched it in.
    – John Doe
    Commented Sep 3, 2019 at 17:28
0

Every answer here fully satisfies the OP's question. Just for the sake of completeness, the answer can be found in the original movie script:

https://sfy.ru/transcript/back_to_the_future_ts

Script:

Doc: ...Come here, I'll show you how it works. First, you turn the time circuits on. This readout tell you where you're going, this one tells you where you are, this one tells you where you were. You input the destination time on this keypad. Say, you wanna see the signing of the declaration of independence, or witness the birth or Christ. Here's a red-letter date in the history of science, November 5, 1955. Yes, of course, November 5, 1955.

Marty: What, I don't get what happened.

Doc: That was the day I invented time travel. I remember it vividly. I was standing on the edge of my toilet hanging a clock, the porces was wet, I slipped, hit my head on the edge of the sink. And when I came to I had a revelation, a picture, a picture in my head, a picture of this. This is what makes time travel possible. The flux capacitor.

6
  • 2
    Which part of the script explains it?
    – Valorum
    Commented Sep 3, 2019 at 18:23
  • 1
    Also, this is a transcript, not a script.
    – Valorum
    Commented Sep 3, 2019 at 18:24
  • 3
    Hi, welcome to SF&F. When providing a reference (link) to information that answers a question you should always quote relevant portions in your answer in case the link stops working in the future. Please read How to Answer.
    – DavidW
    Commented Sep 3, 2019 at 18:32
  • 1
    Some obvious typos in there...
    – ErikE
    Commented Sep 4, 2019 at 22:49
  • 1
    What does this answer state that the previous answer with 100 score does not?
    – Skooba
    Commented Sep 5, 2019 at 14:40
0

There's the stated reason

Doc: Say, you wanna see the signing of the declaration of independence, or witness the birth of Christ. Here's a red-letter date in the history of science, November 5, 1955. Yes, of course, November 5, 1955.

Marty: What, I don't get what happened.

Doc: That was the day I invented time travel. I remember it vividly. I was standing on the edge of my toilet hanging a clock, the porcelain was wet, I slipped, hit my head on the edge of the sink. And when I came to I had a revelation, a picture, a picture in my head, a picture of this. This is what makes time travel possible. The flux capacitor.

... and there's the real reason

Doc knew that Marty went back to November 5, 1955 because he'd already experienced the 1955 events. He also knew, from the letter, that the Libyans were coming and that this would initiate Marty's journey to the past. So he set up the necessary conditions.

5
  • 7
    Time-travel and timelines doesn't really work like that in "Back to the Future" universe. They're don't have "Novikov self-consistency principle", and Marty definitely returned not in the same 1985 he left. In the second movie Doc even shows scheme of how it works.
    – user28434
    Commented Sep 5, 2019 at 9:00
  • If Doc already knew the letter and all that, then thats right it is not the same 1985 , Im asking of this 1985 (the original)
    – riccs_0x
    Commented Sep 5, 2019 at 14:28
  • 2
    Definitely not the same 1985. When Marty crashed the Delorean in 1955, he took out one of the little pine trees. When he got back at the end, the mall was now called "Lone Pine Mall" instead of "Twin Pines Mall".
    – Omegacron
    Commented Sep 5, 2019 at 16:02
  • @Omegacron, then thats not the same 1985, bacause at the original Doc know nothing about the letter, the Lybians, etc. If it would then he knows he traveled back to 1955, go back, etc and all lost becomes sort of a non sense, why to make all if he already know the end?
    – riccs_0x
    Commented Sep 5, 2019 at 17:26
  • So Perhaps the date programmed isnt by chance.
    – riccs_0x
    Commented Sep 5, 2019 at 17:27

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.