Terminator 2

[A Black Falcon]

Think of a loop that isn't a paradox working this way. Let's say the events of the time travel LEAD to the event that sent them back in time to begin with. If the future events have nothing to do with the past, what, would the past suddenly fill up with more and more copies of the time traveller? Think about it. If you are saying the past "just is", that the person spawned out of nothingness in the paradox world, then there's no connection with the future. In other words, the person in the future travelling back in time has no connection with the version that came out of the time portal, and that means that when the future guy steps in, he steps out along with another one of himself at the same time, and that happens infinitely.

*Attempts to understand paragraph*

*Tries again*

... Man, I hate time travel...

Think about it. If you are saying the past "just is", that the person spawned out of nothingness in the paradox world,

No, they were spawned from a different future when it still existed. Just because it doesn't mean that that changes the past too.

This is a standard time-travel device, really. Changing events only changes things AFTER the change, not anything before. I remember a series of books about the Adventures of the Time Patrol, whenever something was changed people stationed at times before the change would have to go fix it to make the proper future exist again.

Does this mean that you could potentially create a situation where there are several of the same person in the same time? Perhaps, depending on your other rules, yes... and yeah, that could be horribly confusing and easily abused, if time travel was easy and not controlled. But just because that's so doesn't invalidate this concept of time travel.