Questioner
When you started writing Cosmere novels, how much of it had you outlined? How far ahead had you thought?
Brandon Sanderson
When I started writing Cosmere novels? When I started started, I was a teenager. Totally hadn't thought very far ahead. When I was an adult and I was writing them, I wrote one when I was like 20, and I had an inkling, and I played around with things. The first one that I wrote with a real, conscious eye toward the cosmere was Elantris. So the ones that have been published, yes. But when I first started, I had a little bit of an inkling.
Questioner
Have you ever backed yourself into a corner with it?
Brandon Sanderson
Not yet! I have backed myself into corners by saying things to fans that I've already changed in my notes and hadn't realized I had, and stuff like that - I do that all the time. But usually when I do that, I just tell them. "Ah, I'm sorry, I just changed this, guys." I'm still convinced that Stayer and Stepper - that [Robert Jordan] didn't know those were two different horses. I'm utterly convinced that he made the mistake, and then just covered it. Because that's the sort of things we writers do.
One of the ones I’ve been working on a lot lately is, how much can you affect things that are Invested with other magic systems? Should it be not at all, should it be a little bit, should it be…? But then I have to go back to Mistborn, and I’ve got canon here, where people are pushing and pulling on things that are Invested, but I tried when I was even writing Mistborn to make sure that the someone was drawing on the Mist, or had extra power for some reason before they were pushing on… and so I left myself that room, but at the same time I’ve established that you can do it, so anyway.