Philosophies of Time Travel

The Philosophies of Time Travel

Welcome to the future! Today is ‘Back to the Future‘ day: the date in the future that Marty McFly and Doc Emmett Brown set in their DeLorean time machine in the famous film franchise.

The original Back to the Future played with one of the fundamental curiosities in time travel, the grandfather paradox. By altering the past, Marty finds that he has changed the future – including the fate of his own family, ‘erased from existence’ as Doc Brown notes.

These cause-and-effect oddities provide a lot of the joy (and confusion) in time travel tales, as well as providing fresh plot structures for writers. Here’s a few of my own film favourites from the past decade or so – as spoiler-free as possible for those who haven’t checked them out yet, and still containing some of my own confusion. Please do feel free to educate me, or mention your own favourites, in the comments section.


Looper is a gangster-style tale in which hit-men are richly rewarded for killing individuals sent back from future crime bosses (a rather convoluted way of ensuring there is no evidence), with the understanding that at some point their own future self will be sent back for killing, in order to ‘close their loop’.

When looper Gordon Joseph-Levitt’s future self Bruce Willis returns though, he escapes, with a plan to fundamentally change the future by killing off the future crime boss when he is a child. The culmination of the film comes with a twist that will probably blindside many viewers – though the use of the grandfather paradox in this film is possibly inconsistent given that Willis’s earlier interactions with his younger self would themselves have already changed his history, and therefore himself, prior to the culmination. Perhaps I’ll just chalk this one up to alternative timelines…


This wonderful film from Australia’s Spierig brothers (also known for Daybreakers) is based on the Robert Heinlein short story All You Zombies. It takes the idea of interacting with your own past to create the future as far as is perhaps possible (there are so many puns I could drop here, but they would unfortunately be major spoilers).

Highlighted by some wonderful acting by the stars, Ethan Hawke and especially a fantastic performance from Sarah Snook, Predestination takes its name from the time travel paradox of the same name (also sometimes called the ‘bootstrap paradox’ – where future events are somehow the cause of events in the past. In the end the hero’s story is a self-contained loop, an ouroboros – and given the complexity of the tale (here’s a graphic for those who have seen the movie – warning, SPOILERS), hats off to the film-makers in how beautifully they pull the entire thing off.

Somehow this film slipped under a lot of people’s radars – make sure you put it on your list of movies to see.


Primer is the ultimate time travel film for geeks. By that, I mean it’s a brilliantly written plot, and wonderfully executed, but perhaps slightly at the expense of the human element of the story, and certainly at the expense of casual watchability (timeline graphics such as this one and this one – SPOILERS – meant to explain the film are themselves largely indecipherable complex tangles).

A short, independent film created by Shane Carruth (also known for Upstream Color), Primer perhaps stands upon the heap for brain-frying levels of timeline weirdness – a must-see for any enthusiast of the genre. And at a reported budget of just $7000, it shows that you don’t need Hollywood’s hundred-million dollar budgets to tell a great science fiction story.

Other films or novels?

I’d also give honourable mentions to the likes of Donnie Darko, Edge of Tomorrow and Deja Vu as relatively recent films that have played with time travel ideas (and 12 Monkeys as another favourite from…ahem…further back in time), although perhaps not to the extent that the films above did. Do you have a favourite story – film, novel, or comic – that utilises time-travel weirdness? Let us, and other readers, know in the comments – we’d love to check them out!