Primer: Why it Works

A series in which I oversimplify one concept from a work of literature to make you a better writer.

Time Travel

Time travel sucks as a genre. It’s a bit of a pet peeve of mine. Yes, the whole genre.

Everyone knows about the grandfather paradox: if you travel back in time and kill your grandfather before he conceives with your grandmother, there would be no you to go back in time and kill him.

But many people misinterpret the paradox as being about specific inconsistencies you can trace, when in fact it’s more of a chaos theory issue: the tiniest change of the past could radically change the “present” in unforeseeable ways.

This could happen if the person goes to the past and doesn’t even physically interact with anyone. Merely being seen by a person could alter their day, which leads to change after change after change…

Pretty much every book or movie I’ve seen with time travel has been terrible. It either ignores this problem, has the problem but tries to explain it in an unsatisfactory way, or it succeeds in explaining it but destroys the story in the process.

I honestly believe no one should ever write a time travel story because it’s going to be a disaster no matter how hard you try.

It’s not worth the effort. If I ran an SF magazine, my first rule of submissions would be: no time travel stories (rule 2 would be: no first-contact stories).

But then we wouldn’t have Primer, which actually kind of works.

primer movie

Primer Movie Explained

The first thing is that when the main characters go back in time, it’s accidental. This is very important in not creating a causal loop.

If your character has to go back in time to change something to save the world, then when they succeed, there will be no reason for them to go back. Hence, the paradoxical loop. Making the initial travel accidental is an interesting way to solve that problem.

The Box

The second thing is the physicality. There’s something strange about old-school time travel (think The Time Machine), where a person and/or machine materializes out of nowhere in the past.

This doesn’t seem like a problem until you think about it a lot. If the machine wasn’t there in the past, what does it mean that it suddenly is? This is a much deeper philosophical issue than people give it credit for.

Primer brilliantly fixes this problem by making the machine a box that you have to turn on at the time you want to travel back to. So if you turn on the box right now, you can’t use it to travel back before that time.

You get in the box at the future time and travel back without running into the physicality problem. You are physically in the box the whole time you’re traveling back.

Isolation

Primer also solves the problem of interacting with the world by isolating themselves so that they only interact with the world once. This means they aren’t changing the past. They’re living it out for the first time the time they travel back.

But here’s the most important reason Primer succeeds.

It is way too confusing to ever know if they’ve run into a paradox. It succeeds because there’s always more to figure out on subsequent viewings.
This sounds like cheating: make your story so confusing that no one knows if there’s a problem. It sounds like bad writing.

But let’s put it in comparison to every other time travel story where it’s immediately obvious that it all falls apart for philosophical and paradoxical reasons. I’d rather be left with the fun journey of trying to piece it together than a pile of unsatisfying nonsense.

If you’ve read a book that handles time travel well, I’d like to hear about it. Despite being a pet peeve of mine, I still masochistically seek them out in hopes of being proved wrong someday.

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