You've made a hell of a mess of all this. The premise presented is simple. The past is fixed, the universe is consistent, if you travel back in time that always

You've made a hell of a mess of all this. The premise presented is simple. The past is fixed, the universe is consistent, if you travel back in time that always happened. You're saying there's a puzzle about something that the premise at hand simply says is impossible. You might as well imagine being able to create energy out of nothing and then say that's a puzzle in a universe in which we have conservation of energy. Just because you can imagine something impossible doesn't make it a paradox. And I’ll reiterate: I accept all of these premises No you don't. You keep saying "but what if you go back and change the past?"