CHAPTER 6
Adventures in Mental Time Travel
Let Marty McFly run into Marty McFly
Thanks to the success of the three Back to the Future movies, our go-to source on the rules of time travel is more likely to be Doc Brown than Dr.
Stephen Hawking. The first rule, emphasized by the trilogy and repeated by nearly every time-travel movie since, is “Whatever you do, don’t meet up with yourself!” Doc Brown (Christopher Lloyd) explains to Marty McFly (Michael J. Fox) in Back to the Future: Part II (1989) that “the encounter could create a time paradox, the results of which could cause a chain reaction that would unravel the very fabric of the space-time continuum and destroy the entire universe. Granted, that’s the worst-case scenario. The destruction might, in fact, be very localized, limited to merely our own galaxy.”
“Don’t meet up with yourself” has become an unquestioned element of the “science” of time travel. In Timecop (1994), because “the same matter can’t occupy the same space at the same time,” Jean-Claude Van Damme’s character destroys the villain by pushing his past and future versions together. The villain turns into a liquefied blob and disappears from existence.
In real-life decision-making, when we bring our past- or future-self into the equation, the space-time continuum doesn’t unravel. Far from turning us into a liquefied blob, a visit from past or future versions of us helps present- us make better bets. When making decisions, isolating ourselves from thinking about similar decisions in the past and possible future