The past: a new and uncertain world. A world of endless possibilities and infinite outcomes. Countless choices define our fate: each choice, each moment, a moment in the ripple of time. Enough ripple, and you change the tide... for the future is never truly set. - Charles Xavier, [X-Men: Days Of Future Past](tag:203942)
Not too long ago, I published what I consider to be the (currently) correct versions of both the Original and Revised timelines in the X-Men Cinematic Universe, both of which you can read here. However, there still exists a major problem, not just for the timelines I've created, but for every single person who ever attempts to work out even a single sequence of events for the X-Men universe: continuity. The films are notorious for creating numerous continuity errors, from confusingly reusing names/powers ("Emma" Silverfox in X-Men Origins and "Emma" Frost in X-Men: First Class) to casting different actors to play the same character in different time periods (I mentioned Psylocke's use in 2006 and in the 1980s in an update on the timeline post).
While it's easy to simply chalk this up to lazy filmmakers not paying attention and screwing up the sequence of events in the films, I believe there's actually a logical way to explain away most, if not all, of the continuity errors. To do that, we'll have to take a look at time travel in the X-Men Cinematic Universe and how the flow of time in that universe is affected by time travel, then apply it to the symmetry of time and the ripples caused from disturbing the natural flow of things.
The Simple(ish) Stuff
First, let's talk about the easier to explain aspects of Logan's time travel adventure. Just before she sends Logan back through time in Days of Future Past, Kitty Pryde somewhat explains "the rules" of time travel with this line:
"Basically your body will go to sleep while your mind travels back in time. As long as you're back there past and present will continue to co-exist. But once you wake up, whatever you've done will take hold and become history. And for the rest of us it will be the only history that we know. It will be like the last 50 years never happened. This world. This war. The only person who will remember it is you."
There's a number of different fields and ideas present in this one line, but let's start with the simplest. Clearly, the entire Days of Future Past film is a gigantic example of the Butterfly Effect, or the changes caused by various factors made in a specific point in space and time. I wrote up a sort of joke example of this, using both modern versions of Fox's Fantastic Four as the focal point, a while back on my website, which you can read here. You could also watch the quick lesson Jeff Goldblum's character gave about the Butterfly Effect and Chaos Theory in 1993's Jurassic Park, as linked below.
Now, let's apply this to Days of Future Past. Think back to when Logan attacked those thugs when he first arrives in 1973. Let's assume that, in the original version of events, Logan killed all of the thugs in the room, leading him to the decision to leave the mob and re-enlist in the military/serve another tour of duty and fight in the Vietnam War (which would eventually lead to X-Men Origins: Wolverine and the rest of the Original Timeline).
However, because this time he stole a car and traveled to the X-Mansion (leading to the rest of the events of Days of Future Past), now we have an entirely new timeline. This time around, Logan (so far as we know) never met the original William Stryker, never received his adamantium implants in the same manner we saw before, never lost his memory from adamantium bullets, and never spent 15 years trying to figure out who he really is. Keep in mind that this is just one of many different changes that have occurred due to Days of Future Past.
In a way, you can think about this as something like Back to the Future, in that changes in the timeline's future are more severe the more the time traveler meddles in past events. However, keep in mind that the X-Men films differ ever so slightly in exactly how time travel affects a timeline. While most people, myself included, have been trying to see time as a simple forking path diagram, what I realized is that we should be looking at it more like water (or, if you'd prefer, a "big ball of wibbly wobbly, timey-whimey stuff"). We'll get into more detail with this further below.
A Little More Detail
This is where things start to get a little more complicated, but bear with me.
Time is not, has not, and never will be, a simple, one way direction. It only appears that way because human beings aren't equipped to see past, present, and future all at once. These concepts are man-made to describe different aspects of the here and now. Picture it like a large wall at the end of a corridor. You can't go backwards, and you know there's something on the other side of the wall down the hall, but you can't tell for sure exactly what's back there. Therefore, a time traveler is an individual who is not only able to "peek around the corner" and see what's ahead, but can also choose to walk back the way they came.
Another way of putting it is through the television show Doctor Who. If you're a fan of the show, then you should already understand the reference I made with the clip in the last section. If not, that's okay. I've got you covered:
What the good doctor is explaining in the clip is the concept known as "retro-causation", otherwise known as retrocausality. Generally speaking, it's the idea that effects can happen before whatever caused them takes place.
Remember how I said earlier that time is like water? It flows, and if you drop something into it, you'll create a number of ripples. The size and reach of these ripples depend on the size of the object dropped in and the force it has when it hits the water. This is where my theory comes in: why do the "ripples" only occur in one direction through time? More importantly, why should we believe that they do? Much like water, ripples don't just extend in one direction in time.
Now, let's apply all of this to the X-Men Cinematic Universe, using Nightcrawler's birthday as an example. In the Original Timeline, I've established it to be in 1956, given that X2: X-Men United takes place in the 1990s. There's a clear correlation between cause and effect here: Nightcrawler was conceived (the cause), leading to his birth in 1956 (the effect). Retrocausality would then make it so that Nightcrawler's birth would take place before his actual conception date, which could help explain why his new birth date is in 1964 (in the Revised Timeline).
Remember what I said before about the forked timeline diagram? These two different birthdates are before Logan's arrival, and shouldn't be affected by Days of Future Past, rendering the idea of retrocausality impossible. However, if we believe that widespread ripples can and do cause retrocausality, then this gets cleared right up. To sum it up, if time is like water, Logan is like a rock being dropped into the water. The ripples caused from him landing are the changes in time.
As I've stated before, I think it's very clear that the ripple effect exists when it comes to time travel in the X-Men Cinematic Universe. Not only that, but depending on the actions a time traveler makes in that universe, there must be an equal amount of ripples changing things in the past.
Rather than using the plot hole creating fork diagram, if we were to apply this idea to the X-Men Cinematic Universe, we can then make sense of the other changes occurring. Logan attacking some thugs in a random room when he probably shouldn't have? Might make for a slight amount of ripples and minor changes, such as changing around some people's ages. Stopping the Sentinel program from taking off in the first place? Now Xavier and Magneto don't meet at 17, they meet as fully grown men. I could pull up more examples, but the point is this: Logan wouldn't just be changing the future when he went back in time. Thanks to the huge amount of changes he would make to the timeline's future, Logan would also be changing the past.
All that having been said, even though I personally think this is the best way to explain away the problems with the X-Men timelines, I'd still ask that you keep in mind that this is all just a fan theory, and that nobody has confirmed or denied any of this. As with my post on the X-Men Cinematic Universe timelines, I'm considering this a work in progress. Even though I'm still looking it over and will fix any problems I find in it, I encourage everyone reading this to point out any flaws so they can be fixed ASAP.
What do you think about this interpretation of time and time travel in the X-Men universe? Let me know in the comments below, or through Twitter at @comicsvsworld. While you’re at it, don't forget to check out my website, Comic Books vs The World, for even more comic book related content.