I thought it might be a more Hawking style ending - Gordon Levitt kills self, having no effect on Bruce Willis whatsoever in current reality. LOL @ Dr. Who and Emmett Brown.

Boosting this quality contribution up in the Hot Listing - declared quality by dystopianfuturetoday.

The original stroryline is a chicken or the egg paradox.

If old Joe's wife is murdered by the Rainmaker and yet him going back in time causes this to happen in the first place, which was the originating cause of it all? If the two are interdependent on each other occuring, the answer has to be neither.

Another problem with the ending is that, in the original Bruce Willis' timeline, nobody goes back to try to kill the kid. The kid ends up growing up with his mother, and still becomes the rainmaker, meaning that his mother's positive influence did not matter. So it makes Gordon-Levitt's sacrifice completely meaningless.

Fuck this stupid overrated bullshit movie. (fuck INCEPTION too)!

EVERYONE GET DAWON!! #&@*($*(@&%(@!#@!%$

the only way to explain this movie is with a before and after universe. where universe one story line takes place, and another where the other version of the story happens, we watched timeline B. where the people are sent back to and killed. it IS possible that the mom was killed by some other gangsters and the kid goes awol in timeline A, the movie would have taken place, and that by sending people back are in fact sending them to the alternate version of timeline a.

or

in theory, if you follow how quantum states work, if sending someone back in time, you are actually removing him from our existence and creating a world for that person to appear in separate from ours but still within it, or kinda imbetween us, but not visible to us, and that 2nd world would then only exist because of that person, making sense that what happens happens, but by killing himself, he no longer is able to exist in that new world, forcing the matter in the new world to "overwrite" the original where he was sent from.
kinda like how quantum matter does not decide what it wants to be until it is measured. that stops world 1 from making sense, erasing world 1 with the new world 2. this is most likely the only way to prevent the time loop issue caused by most "time travel" movies.
or, in star trek terms, world 1 is real, world 2 is not. unless something happens in world 2 that breaks world 1. making world 2 the most likely outcome for the future. erasing world 1 and world 2 becomes the world.

or even simpler, world 1 happens, then interferes, creating a 2nd image of itself, until something happens in world 2 that breaks world 1s existance, they both exist, and don't. until something happens to tell matter in those worlds what happens. so until that point where world 2 overwrites world 1. both exist and world 1 is still free to interefere with world 2. or how ever many versions there are. you send someone back, they are killed, and both worlds are able to agree with the outcome merging and continuing as if nothing happened.

if you follow... i think i got ahead of myself with this one. this is all of course a movie.

In the multiverse theory of reality, anything that can happen, happens on some plane of the brane (not precisely the theory, but it rhymes). Time travel simply places you in one of those possible timelines where history is such that your presence cannot create a paradox. All those disappearing people and body parts couldn't/wouldn't happen. The film takes a more determinist and uni-universe slant, I guess.

Still a fun movie. I don't have a problem with science fiction movies taking creative liberties with the science.