Re: Time travel paradox (#40710)
by Aeon J. Skoble on August 27, 2004 at 1:53 PM

I mean "certainly" -- Chris, is there no way to edit comments?

Re: Time travel paradox (#40790)
by Steven Horwitz on August 28, 2004 at 11:54 AM

This conversation takes me back... As an undergrad econ/phil double major at Michigan, I took a "Philosophy of Space and Time" course from Larry Sklar, who I later learned is at the very top of the philosophy profession on these issues. I adored that course and Sklar, who was the model of the great scholar AND teacher, as we talked about a whole bunch of cool stuff, these sorts of paradoxes included. I wound up writing my term paper on "The Planet of the Apes" movies, raising just the sorts of issues we're raising here. When I got the paper back, I got a 98/100 from Sklar. I've done a lot of stuff to be proud of in the last 20 years, but that 98 ranks up there with any of them. :)

Re: Time travel paradox (#40727)
by Jonathan Dresner on August 27, 2004 at 4:13 PM

The Time Travel Paradox is a plot line in which there is a single future (multiple branching futures don't have this problem, at least not if they're handled properly). If someone from the future affects the past in such a way as to substantially change the future, then it is unlikely that someone from that future would come back to make the change.

This is sometimes refered to as the "Grandfather Paradox": if you go back in time and kill your grandfather before your parent is born, then you would never exist, and could not, in fact, have come back into the past to kill your grandfather.

Terminator and TimeCop are the worst perpetrators of the paradox, but it's pretty common. Back to the Future has the virtue of being funny about it....

Star Trek's "City on the Edge of Forever" (by Harlan Ellison) skirted it by having them fix the changes, allowing the future to indeed unfold in their direction again, and subsequent Star Treks have (usually) adhered to the dictum that "if you end up in the past, don't change it!" (in later shows, it's called the Temporal Prime Directive, or something like that).

All time best time travel story ever: Robert Heinlein's "By His Bootstraps", in which time travel is a closed circle of causality.

Re: Time travel paradox (#40737)
by Dan Schmutter on August 27, 2004 at 5:42 PM

One film which does a nearly perfect job with respect to time travel is Twelve Monkeys -- a highly underrated film in my view.

If you pay close attention to the various instances of time travel in the film (and there are quite a few), they only run into the paradox once. In every other instance it is done correctly.

That is why it is typically a good idea to simply avoid time travel in the first instance, unless the author is going to pay particularly close attention, which they almost never do, but which the author clearly did in Twelve Monkeys.

By the way, I disagree that The Terminator is especially bad in this regard (unless you mean T2 and T3 in which case I agree). The paradox presented in The Terminator is not an essential plot element. [Spoilers follow.] If the Reese-as-Sarah-Connor's-son thing is removed from the film, the story remains intact. It's annoying, but it is forgivable because the entire film doesn't depend on it. Its simply thrown in there for its twist appeal.

Remove it and the film is just as good, if not better.

Dan