It makes sense…in theory. Spoilers if you’re not up to date on the show.
This week’s episode of Game of Thrones saw Bran tragically turn young Wyllis into Hodor, confirming the idea that he can affect events in the past.
…or can he? Because Hodor was Hodor before Bran went back in time, so HOW DOES THAT MAKE SENSE?
As Reddit user Jdylopa suggests, it seems the « time travel » on Game of Thrones is following the Novikov self-consistency principle, which means only one timeline exists and all events are fixed.
Everything that has happened was always going to happen. Those who travel into the past aren't affecting events – they were always a part of them. So Bran didn't actually change anything, he simply acted out his own place in history.