There’s no real working definition of science fiction. There’s this, which I found in the dictionary:

“a form of fiction that draws imaginatively on scientific knowledge and speculation in its plot, setting, theme, etc.”

Seems like a good starting point, but doesn’t define the boundaries very well.  Many might count Resident Evil as a science fiction series. But does that mean that so is Evil Dead or Bride of Chucky? It also makes it difficult with the fantasy overlap. Star Wars certainly doesn’t really draw upon any scientific knowledge, it’s just vaguely spaceship themed. In most respects, it’s just a purely made up universe, just like Lord of the Rings.

And then what about Apollo 13 or Gravity? These films are effectively films that focus on real stories or current-day tech, but happen to be set in space. They don’t really draw imaginatively on scientific knowledge or speculation.

Conversely, films like Eternal Sunshine of the Spotless Mind and The Prestige don’t dress up like a sci fi, but when you stop and inspect the content it unmistakably does match that definition.

Ultimately, it’s extremely difficult to define what should and shouldn’t be included on this list. There could be countless arguments to be had over the inclusion of all sorts of different films, but in the end I don’t think it matters a great deal. I try to stick with the general idea of:

“The content of the movie must extrapolate upon current-day scientific knowledge or ideas’

It also means that I am often quite forgiving of movies that feature a farfetched concept at their heart. That’s OK, because it’s a what if scenario. What if the sun was dying? What if we could delete memories? What if we could travel back in time? The films break when they ask the audience to suspend their disbelief too often, when the internal logic of a film’s universe is contradictory, or when explanations are waved away with a hand gesture.

So it’s that philosophy that I’ve used to create and maintain this list. Yes, there are exceptions for Gravity and Star Wars, the cultural significance of which force their way into my list. Yes, some zombie movies make it in and others don’t – the ones I feel have a kernel of science at the centre do enough to justify their inclusion for me.

It’s unclean and not always perfect, but it’s my list. So there.