Where does a circle begin? Where does it end? Google “bootstrap paradox”

You’re are not the only one to come up with the idea, but that doesn’t really quite work. Simply sending John back to impregnate Jane just creates a baby. It’s a unique baby as it really only has one parent, essentially a clone of Jane. But the baby would not be Jane, but a new person. If you took the baby back to 1945, you would find Jane was already there too, since the two are not the same person. If you swapped the two, the replacement would be genetically identical, and in the same environment might grow up in a similar (but not identical) way, but what would be the point? You already have the original there. If there was an original Jane, born of two ordinary people and you need Jane to be pregnant with herself in the scenario you suppose – How do you create that? I can’t think of a way. This is not meant to be a thing created, but a boot-strap paradox, that can’t be explained by an outside cause. Self-caused, uncaused. It always was, it always will be.

He does though. He’s right there in the story twice and sometimes three times at once. (4 times if you count that Jane is pregnant with Jane when barkeep John comes to pick up younger John at the park with Jane). What – you have no problem with him being his own mother and father but this is impossible? He has a fist fight with hisself. He has sex with herself, She give birth to herself. That’s a whole lot of co-existing.

“the rule that two of the same entity can’t exist at the same time, ” That’s only a rule in some stories. it’s nowhere a rule in this story. Through much of the movie there are 2 Johns. Jane and John are the same person and they coexist along with a second John for a while too. Jane is literally pregnant with herself for 9 months. That “rule” has no application at all here, since it not a thing unless the author says it’s a thing

you know you love me for spoiling it for all!!!

I hate u.

It was a joke 🙁

That is true unless it is defined that you have to remember each time you reach that older age, that on that same day to go back at that specific time in your life and tell yourself. So you establish that the first time that you did time travel. Then each time in your life you must do the same thing. Remember you can not disrupt the past in time travel.
So after your first time travel back to the past, the recruitment is just the action of doing so, not an actual recruitment.

if you took your younger male self back in time to have sex with an even younger self who is a female and they make a baby together who would that child you give birth to be?

they would follow the same path if yourself from the future came back in time to try to manipulate you to do things the way your future self would want you to