“The Door” is the most important episode of Game of Thrones since the one where Daenerys took control of the Dothraki horde. Wait, that was just one episode ago. Nevertheless, it’s still a hugely important episode and—spoilers ahead—unveiled Bran in his full power. With the death of the Three-Eyed Raven, Bran has become the last greenseer. His powers are clearly huge. And yet one thing is very clear—Bran cannot change the past. His power is slightly different: He can create the present that already exists.

Game Of Thrones Season 6: Bran Can Define The Present, But Not Change The Past

Let’s take a careful look about what exactly happened with Hodor there. Bran was exploring the past with Max von Sydow when the White Walkers burst into the tree-cave. The Night’s King killed the Three-Eyed Raven as Meera and Hodor pulled Bran the heck out of there. And Meera yelled to Hodor to “hold the door.” And Hodor heard her, through Bran, in the past. And it destroyed his mind, making him Hodor for the rest of his life. It’s an epic moment, apparently straight out of the books. It’s the first moment that shows Bran’s power.

Hodor’s disfiguration in the past because of events in the present reveals several things. First, it proves that Bran is not just seeing the past. He is traveling to the past, because his presence there has a real effect on the past. But here’s the key point: Bran didn’t actually change the past. He set the past on a course that would become the present. The existing present time didn’t change. Hodor didn’t become Hodor just now; he’s been that way all along. Yes, that was because of Bran. But it was always done. As the Three-Eyed Raven has said before, the past is already written.

It’s a critical distinction. It means that Bran doesn’t have the power to, say, bring Ned and Robb Stark back to life. Because Ned Stark is dead, and so is Robb. He can’t allow himself to walk again. But he could, for example, have made the Mad King mad—because, in the present timeline, the Mad King really was mad. It’s a classic time loop paradox. Everything Bran has done in the past has already been done, and we can already feel the effects of all those actions in the present. So he can’t really change the past, and he certainly can’t change the present. It’s more accurate to say “Bran can have changed the past already.” His actions in the past, yet unseen, may have set events on their current course (for the closest other analogue in fantasy, see the Dragonriders of Pern series, which explores such paradoxes in depth).

Bran truly has an incredible power. The world of Game of Thrones is, to a yet unknown degree, one that reflects Bran’s will. He can’t change it… but he may have made it in the first place.