You lose a leg in a boating accident and 10 years later they invent time travel. You travel back in time (one way only) and tell yourself not to go on the boat that caused you to lose your leg. Your past self listens to future self and avoids the boat.
The outcome of this action would be:
1. Your future self would immediatly dissapear as without the boating accident you would never travel back in time to tell past self about the accident. (Looper, Back to the Future time travel ideology)
2. You would not have the accident but your future self would be stuck in the past without a leg for the rest of time. (Terminator time travel ideology)
3. You would lose the leg anyways. Without the boating accident your future self would never go back in time, and since that has to happen you have to lose your leg. (Timemachine time travel ideology)
4. Other - please explain