Probably you have already talked about this topic in many threads. In Asos Jaime, on his way from Harrenhal to KL, makes a dream that influence his decision to come back and rescue Brienne. You can read it in a psychological way and it makes perfect sense. You can read it as a rapresentation of jaime's past present and imminent future. You can read it as a prophecy in long terms. but jaime was sleeping on a weirwood stump. Does it indicate the dream is necessarily prop