876
I now know why you cry
(lemmy.world)
General rules:
Exceptions may be made at the discretion of the mods.
Many versions of fictional time travel that allow backwards travel suggest that the travel cannot happen further back than the initial use of the time machine.
Perhaps my favorite example of this (in terms of narrative, if not logic) is a time machine that is turned on, only to immediately receive a note saying "turn it off RIGHT NOW."